I am using QB Online and am struggling with one solitary transaction on the bank feed. The amount on the feed is eg £20 but when I try to match it to the corresponding Customer payment a message pops up : 'Partially matched £40 remaining out of £20'.  This makes no sense on a couple of levels! The amount on the feed corresponds to the actual paper bank statement which corrresponds to my records.

Every other transaction on the bank feed has matched the amounts.

I am at a loss as to what has happened and therefore, what to do about it. I have refreshed the feed, deleted and re-posted the Sales Receipt, logged out and logged back in again. 

Any suggestions?