Troubleshooting

Sometimes you may find yourself facing a problem that doesn't have a clear solution. These troubleshooting tips may help you solve problems you run into.

Issues on the Exchange

INSUFFICIENT_OUTPUT_AMOUNT

The transaction cannot succeed due to error: BlueHorizonRouter: INSUFFICIENT_OUTPUT_AMOUNT. This is probably an issue with one of the tokens you are swapping.

the transaction cannot succeed due to error: execution reverted: BlueHorizonRouter: insufficient_output_amount.

You're trying to swap tokens, but your slippage tolerance is too low or liquidity is too low.

Solution

1. Refresh your page and try again later.

2. Try trading a smaller amount at one time.

3. Increase your slippage tolerance:

   1. Tap the settings icon on the liquidity page.

   2. Increase your slippage tolerance a little and try again.

4. Lastly, try inputting an amount with fewer decimal places.

Reason

This usually happens when trading tokens with low liquidity.

That means there isn't enough of one of the tokens you're trying to swap in the Liquidity Pool: it's probably a small-cap token that few people are trading.

However, there's also the chance that you're trying to trade a scam token which cannot be sold. In this case, PancakeSwap isn't able to block a token or return funds.

INSUFFICIENT_A_AMOUNT or INSUFFICIENT_B_AMOUNT

Fail with error 'BlueHorizonRouter: INSUFFICIENT_A_AMOUNT' or Fail with error 'BlueHorizonRouter: INSUFFICIENT_B_AMOUNT'

You're trying to add/remove liquidity from a liquidity pool (LP), but there isn't enough of one of the two tokens in the pair.

Solution

Refresh your page and try again, or try again later.

Still doesn't work?

1. Tap the settings icon on the liquidity page.

2. Increase your slippage tolerance a little and try again.

Reason

The error is caused by trying to add or remove liquidity for a liquidity pool (LP) with an insufficient amount of token A or token B (one of the tokens in the pair).

It might be the case that prices are updating too fast when and your slippage tolerance is too low.

BlueHorizonRouter: EXPIRED

The transaction cannot succeed due to error: BlueHorizonRouter: EXPIRED. This is probably an issue with one of the tokens you are swapping.

Try again, but confirm (sign and broadcast) the transaction as soon as you generate it.

This happened because you started making a transaction, but you didn't sign and broadcast it until it was past the deadline. That means you didn't hit "Confirm" quickly enough.

BlueHorizon: K

The transaction cannot succeed due to error: BlueHorizon: K. This is probably an issue with one of the tokens you are swapping.

Try modifying the amount on “To” field. Therefore putting "(estimated)" symbol on “From”. Then initiate the swap immediately.

This usually happens when you are trying to swap a token with its own fee.

BlueHorizon: TRANSFER_FAILED

The transaction cannot succeed due to error: execution reverted: BlueHorizon: TRANSFER_FAILED.

Make sure you have 30% more tokens in your wallet than you intend to trade or try to trade a lower amount. If you want to sell the maximum possible, try 70% or 69% instead of 100%. Caused by the design of Restorative Rebase tokens like tDoge or tBTC. Understand how restorative rebase tokens work.

Another possible cause of this issue is the malicious token issuer just suspended the trading for their token. Or they made selling action only possible for selected wallet addresses. Please always do your own research to avoid any potential fraud. If the token you are trying to swap but failed with this error code is coming from an airdrop, that is most likely a scam. Please do not perform any token approval or follow any links, your fund may be at risk if you try to do so.

Transaction cannot succeed

Try trading a smaller amount, or increase slippage tolerance via the settings icon and try again. This is caused by low liquidity.

Price Impact too High

Try trading a smaller amount, or increase slippage tolerance via the settings icon and try again. This is caused by low liquidity.

estimateGas failed

This transaction would fail. Please contact support

Solution

If you got this error while removing liquidity from a BNB pair:

Please select "Receive WBNB" and retry.

If you got this error while trying to swap:

Please contact the project team of the token you're trying to swap. This issue must be resolved by the project team.

Reason

This issue (while swapping) is caused by tokens which have hard-coded the V1 Blue Horizon router into their contract.

While this practice is ill-advised at best, the reason for these projects having done this appears to be due to their tokenomics, in which each purchase sends a % of the token to LPs.

The projects affected will likely not work with the V2 router: they will most likely need to create new versions of their tokens pointing to our new router address, and migrate any existing token holders to their new token.

We recommend that any projects which created such tokens should also make efforts to prevent their users from adding them to V2 LP.

Cannot read property 'toHexString' of undefined

"Unknown error: "Cannot read property 'toHexString' of undefined"

When trying to swap tokens, the transaction fails and this error message is displayed. This error has been reported on mobile devices using Trust Wallet.

Solution

1. Attempt the transaction again with increased slippage allowance.

2. If 1. does not resolve your problem, consider using another wallet such as SafePal for your transaction.

Reason

This usually happens when trading tokens with insufficient slippage allowance on Trust Wallet.

The exact details of the problem are still being investigated.

Execution reverted: TransferHelper: TRANSFER_FROM_FAILED.

The transaction cannot succeed due to error: execution reverted: TransferHelper: TRANSFER_FROM_FAILED.

When trying to swap tokens, the transaction fails and this error message is displayed. This error has been reported across platforms.

Solution

1. Check to make sure you have sufficient funds available.

2. Ensure you have given the contract allowance to spend the amount of funds you're attempting to trade with.

Reason

This error happens when trading tokens with insufficient allowance, or when a wallet has insufficient funds. If you're trading tokens with Restorative Rebase like tau assets tDoge or tBTC, make sure you understand how they work first with this guide to Rebase tokens.

Other issues

Provider Error

Provider Error No provider was found

This happens when you try to connect via a browser extension like MetaMask or Binance Chain Wallet, but you haven’t installed the extension.

Solution

Install the official browser extension to connect, or read our guide on how to connect a wallet to Blue Horizon.

Unsupported Chain ID

Switch your chain to Binance Smart Chain. Check your wallet's documentation for a guide if you need help.

Issues buying SAFEMOON and similar tokens

To trade SAFEMOON, you must click on the settings icon and set your slippage tolerance to 12% or more. This is because SafeMoon taxes a 10% fee on each transaction:

• 5% fee = redistributed to all existing holders

• 5% fee = used to add liquidity

This is also why you might not receive as much of the token as you expect when you purchase. Read more on How to Buy Safe Moon.

Internal JSON-RPC errors

"MetaMask - RPC Error: Internal JSON-RPC error. estimateGas failed removeLiquidityETHWithPermitSupportingFeeOnTransferTokens estimateGas failed removeLiquidityETHWithPermit "

Happens when trying to remove liquidity on some tokens via Metamask. Root cause is still unknown. Try using an alternative wallet.

Internal JSON-RPC error. { "code": -32000, "message": "insufficient funds for transfer" } - Please try again.

You don't have enough BNB to pay for the transaction fees. You need more BEP-20 network BNB in your wallet.

Error: [ethjs-query]

Error: [ethjs-query] while formatting outputs from RPC '{"value":{"code":-32603,"data":{"code":-32000,"message":"transaction underpriced"}}}"

Increase the gas limit for the transaction in your wallet. Check your wallet's documentation to learn how to increase gas limit.

Swap failed: Error: [ethjs-query] while formatting outputs from RPC '{"value":{"code":-32603,"data":{"code":-32603,"message":"handle request error"}}}'

Cause unclear. Try these steps before trying again:

1. Increase gas limit

2. Increase slippage

3. Clear cache