Bittrex

Insufficient balance for the requested action. Mind the fees and the minimum order amount.

Original error code: insufficient_funds

If you get an error showing that your balance is insufficient, it can be based on the following reasons: 

1. The amount placed in your order is less than the minimum trading amount allowed on Bittrex. 
As usual, the minimum Bittrex order value must not be less than the equivalent of $10.

2. The amount of your order exceeds the available balance. 
This can happen in rare cases if something has gone wrong in the TabTrader's prevention mechanism that immediately indicates on the amount being greater than the available balance before the order confirmation.

3. Exchange fees have not been included in the order total, which means that the order consisted of the entire available balance.

The API key has invalid values. Make sure the API key is copied correctly. Or create a new API key.

Original error code: 401.unauthorized

This is a common issue you can have when adding your new API keys. 
The most typical case is that your API public key (in the upper field) has the wrong values in it: not the ones your exchange exposed once the keys were generated. 
It can happen due to an accidental typo or copying some other value by mistake. 

However, this error message can also mean that these API keys no longer exist. 
It can happen because of the keys have been expired or simply removed from your exchange account. 
Make sure your API is still active in your API management settings on your exchange account. 

Your request did not get a response in time. Please try again.

Original error code: 504.timeout

There can be quite a few reasons for this error message to occur due to the obscure nature of the error 504 Gateway Timeout. 
However, there are a few known reasons in our experience when some users may encounter this case: 

1. The request from your device couldn't get a response from the exchange servers due to the unavailability of the latter due to:
Planned maintenance or a global crash of its services, which is usually announced on social media. In both cases only time will help. 

2. The exchange cannot process to the requests from certain geographical zones due to all possible reasons. 
Here your can try using a proxy/VPN and check if it works. 

3. A device's local issues. 
Try clearing cache of the app. In case, this doesn't help, you may consider reinstalling of the app.