Linking Ship to to the bill to site using spreadsheet

Summary:

I need to link the ship-to sites to the bill -to sites for customers load through FBDI. I was trying to using the Spreadsheet to do this. But in the spreadsheet, one column that is mandatory is that Location source system reference. We did not fill this in the FBDI and hence I do not have the value for it. I tried adding site source system reference but it gave an error. Please help

Version (include the version you are using, if applicable):

24C

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