Combo boxes incorrectly updating itself.

[dylcon]

Hello, I have a form that I am using to essentially combine records from a table that holds information about PartNumbers and PONumbers. What is hapening is:



When I use my combo boxes to insert a customer name and their respective part numbers, it works fine. Once I use the PONumber combobox, and make a selection, it clears whatever is in my PartNumber combobox, even though they have the same customer and same CustomerID linked to their numbers. This is obviously difficult to explain, so I have attached my database. It is in the NewPartPOForm.

New Compressed (zipped) Folder (2).zip

[dylcon]

I originally thought that it has something to do with the CustomerID being a FK in both the tblPartInfo and tblPOInfo. What lead me to believe this is, when I select a PO from the combobox, a part is automatically matched to it. I thought it was set up so that the one-to-many relationship exists between the CustomerID and both the tblPartInfo and tblPOInfo, but that may not be true. I also noticed that when I go into tblPartPO, I can add records perfectly OK, as long as a legitimate number is entered that matches an ID for both the POInfoID and PartID.
I am wondering if there is anyone out there who can help me get around this problem. My database needs to be done in about 6 days . Here is an attachment of my relationships as well.