Weltbet Affiliates - Not paying the commission

Weltbet Affiliates listed their brand on our websites for the listing fee (LF) which is paid once for adding the brand permanently on our websites. After that the commission of EUR 2000+ was accumulated (April to July - screen attached). When asked to withdraw the commission they said they would not pay since they paid the LF and we brought only 1 FTD. They said "deduct the LF from the commission" and never answered to us again (screen attached). First of all, even if we wanted to deduct the LF, we can not do it from our side. Secondly, listing fee has nothing to do with the commission as per our agreement, and the amount of FTDs as well. They simply don't want to pay. If needed, we can provide screenshots of all our communication starting from the beginning.

Dear Weltbet Affiliates,

Please let us know if there are any updates regarding this ongoing complaint. Please note that, in case you fail to respond within the given timeframe, we will consider your case unresolved and it will be closed accordingly.

Thanks in advance for your cooperation.