QU No.

07:38 Jun 16, 2016 

I think more context would almost certainly help here.

For a start, what country is this document from? The payment in AED sounds as though it might be the UAE? If so, you might find asking someone from that country to explain it for you may help.
Also, is this (as it seems) part of the document header in some way? Do you actually have the number that follows it? If so, does that give any clues — either from the actual value, or from the number format?
If this is 'proper' EN, there aren't so very many likely contenders for qords beginning with 'Q' in a business context — 'Quality' is one that springs to mind, but not at all clear how that might apply here, nor what the 'U' following it might be... 'Quality Unit'?? Of course, we don't even know if it is a 2-letter abbreviation 'Q.U.', or simply the 'qu...' from the beginning of one word.
I think you may have to ask your customer on this one — or possibly just phone the company in question!