OUTSTANDING INVOICE TO BE PAID

Hi, 

Can anyone help me to understand this?

I have under "finances-documents and invoices" a red notification that never had before, stating that i have an outstanding amount of commision to be paid.

That amount is the amount of the commissions of my 3 last bookings and this was already deducted before paying me the full amount. I mean, if the booking was 60e (for example), I always get paid 54e so that 6 euro are the commission that booking already deduct from me on my payment. 

I do not understand the reason why i have this read statement with the outstanding comision to be paid. 

Anybody could explain?

Thank you so much