> For the complete documentation index, see [llms.txt](https://docs.bancor.network/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.bancor.network/developer-guides/write-functions/trading/trading-troubleshooting.md).

# Trading Troubleshooting

#### Allowance (Approve)

The `BancorNetwork` contract requires token approval to access the user's wallet and execute the transaction. Without an "Approve"/"Allowance" in place, the transaction will not be able to proceed. \
[Read more on how to trigger "Approve"/"Allowance"](/developer-guides/write-functions/transaction-prerequisites/approve-allowance.md) 

{% hint style="info" %}
Some tokens support **gasless** approval by using the permit() function. [Learn more](broken://pages/gwPVUFOcvbYWJKmqWtCA) on trading "Permitted" tokens.
{% endhint %}

#### Token not available

This indicates if the token is not available to be traded on Bancor V3. 

#### Deadline not valid

This indicates that the deadline is set to a time that has already passed. Fix this by changing the value to a future time.