If your exchange API keys expire (such as on Huobi or Binance every 90 days) or when you may experience an error message, such as Invalid API Keys, the best solution is to update your saved API keys for the linked exchange account.
If the exchange supports Fast Connect feature (Binance, OKX), update the API connection with it! Delete the old API keys on your exchange, and update the connection using Fast Connect (Reconnect) feature.
Here is an example of updating the Binance connection with Fast Connect.
It is essential that you update your EXISTING API connection and you don't create a new connection of the same exchange account to 3Commas!
If you delete the old API connection on 3Commas, you'll lose your DCA bots, SmartTrades, trading history, and statistics, and it will disrupt active trades you may have open!
If your DCA bot's trades have a status Error ("Invalid API keys") and you update the existing API connection, your bots' trades most likely WILL NOT BE INTERRUPTED, and they will remain active after the update. If the trades are FAILED, then you will have to recreate them into the Smart Sell or Smart Buy trade (article).
Also, if the API keys expire, SmartTrades will fail, and you will need to recreate them too (article), just take information about the trade from the SmartTrade History page.
The following errors will require you to update your linked exchange account with a new API:
Exchange account is banned.
API key is invalid
API keys are no longer valid or incorrect
Errors like 
Suppose you receive errors like  and an error description. In that case, this is the message from Binance exchange, and it's necessary to contact Binance's support to find out the exact reason for this limitation.
To solve this problem, try to edit your API keys, disable Futures trading permission, and refresh the exchange on the My Portfolio page.
If you receive unusual errors, please head to this article to learn more:
Here is what you need to do.
Create a new API using the exchange's website
Check out these articles below to learn how to create API keys on your exchange if you don't know (or don't remember) how to do this:
Edit the linked exchange account on 3Commas
Open My Portfolio, find the account you want to update, and click on the Update API Key button:
Copy and paste your new API Key and API Secret
Don't forget to update both. You also should update the passphrase, if your exchange requires this, too:
Finish by pressing the save button.