The transfers between your MuchBetter wallet and gaming accounts are free of charge.
The difference in the sent and received amount may be a result of your account settings, where your gaming account has a different currency than your MuchBetter wallet. In this case, the conversion rate will be applied which results in a small difference in the transferred amount.
If both your gaming and your MuchBetter accounts are created in the same currency but you still received a different amount, then we would need to review the transaction in question to be able to provide you with more details. Normally, this difference is caused by the action on the merchant's end. Sometimes the gaming merchant applies, namely, a currency exchange first on their end and then they send us the amount after the currency conversion. We cannot control it because the merchant is applying their own rates and this is not an action we recommend.
The merchant should send us the original amount and, if necessary, we will proceed with the conversion on our end. In this case, you will not lose anything as there would be no FX on our end and you will receive the whole amount. If you noticed that the gaming merchant is not following this suggestion, you can contact them and let them know about it.