Youd have to delete the file and retransfer, or reenter the missing assets.....you cant transfer in overtop of what you've already worked on.

You sure they weren't marked as dispose don the 2019 return? Kinda weird for none of them to transfer.

I agree with Lisa... I have never had an issue like this with the 990 module or any other module with Pro Series Professional, they do an excellent job on the fixed assets...