Daily cash charge not reversed...

Purchased a phone in July, got a daily cash "credit" i guess. Returned the phone also in July and now being "charged" the daily cash. Shouldn't that be a wash? I didn't spend the daily cash. It was all done within the same month and there were no other charges. Or will it take another cycle for it all to balance out. My July Balance at the end of the month has the "charged" daily cash as part of the balance. It is very confusing.