I have an explanation. It does not seem like this is an issue with the exchange.
In version 1.0.7 of the CoinPayments adapter, the deposit fees that the platform incurs are saved into the deposit transaction records. These fees are taken into account since the latest version 3.6.4 of the parent plugin. 3.6.4 was released on the 28th of August. On the 1st of September your user #7 did a withdrawal that was their balance plus the deposit fees (49 DOGE) that were not subtracted from their balance. If you had not applied the latest version 3.6.4. at that time, it would explain the problem. It would also mean that this will not happen again.
My apologies for the trouble.
Is it possible that you had not yet applied version 3.6.4 of the parent plugin on the 1st of September?