I was able to get around the issue and e-file my returns. Apparently, the form gets hung-up if the amounts on Line 5 are negative. This happens under conditions when the taxpayer does not qualify for the credit. It is recommended in the forum thread linked below to delete the amount(s) in Line 1 and then delete the M1SLC schedule completely. It's not needed if you don't qualify for the credit and aren't applying for it.
https://ttlc.intuit.com/community/college-education/discussion/mn-student-loan-i-keep-getting-a-warn...
Good luck!
