IF Statement Assistance

New to the forum and trying to get some help with writing a compound IF statement. I am using an if statement across multiple tabs of a spreadsheet and have the first half but struggling with the second piece.

I am using IF (Customer number from cash tab, customer number, total dollars) to pull in customer total dollars, but I have a few customers on the second piece so it is doubling and sometimes tripling the total dollars.

Is there another piece to this formula I can use to say: If the number is used from the cash tab once, don't use again)?

I appreciate any help.

I have added in a bried example of my issue. The row highlighted on the customer number tab is where I want the second piece of the IF statement to not count in the cash tab info since it was used once already.

We have customers from different locations, but I have no hook to use, and too many lines to sort through, that is why I just trying to say if the customer number is used once already don't use again since they all roll up to one number in the end.

I appreciate the help.

I can't use a pivot table as I am using the tab to feed several other tabs which use pivots. The information also goes out about 9,000 lines. I am trying not to add a ton more logic or tables as it takes a while to do all the calcs.

I really wanted to use an and statment but don't know enough about them to make them work properly.

OK. Pivot Table is out.
Why do you have Customer 139770036 listed twice on the customer number sheet when it is listed only once on the cash tab sheet?
How are you obtaining the list of customer numbers? Shouldn't this be list of unique numbers on the Customer Number sheet?

Well I am trying to limit the data as to 1) not make it to complex, 2) give away company information. We created these unique numbers based on customer number and location.

The problem is that we have multiple contracts with a customer, but the contracts all roll up under one customer number. The one data dumb doesn't have a contract number to differentiate and use as a hook.

So I am trying to build onto the IF statement to only pull in the figure once and ignore if used, so that I don't have to tweek my whole sheet.