To protect the user, W2 Mate automatically detects duplicated tax IDs (social security numbers and employer identification numbers). If you have the same borrower with multiple loans, then you can use the “Allow Duplicate Recipient IDs” feature which gives you the ability to import two or more borrowers with the same SSN / EIN.
Please also remember that W2 Mate has the ability to add 1098 forms manually (you do not have to import). This is also useful If you find out that you need to do a correction / addition after you complete the import process.