I called Lacerte help and the whole situation with 8915F seemed to flummox them!  The diagnostic error code (#0) wasn't helpful for them.  During the session I tried backing out the last 1/3 of my client's CoVID19 disaster related repayment which was showing up on the 1040 in Line 5b as a taxable amount.  I backed out that taxable amount with a negative based on what they had repaid (the final 1/3 of the distribution they took from their IRA in 2020) and made a notation on the line with the negative amount that it was a "CoVID19 disaster distribution final repayment".  I then asked Lacerte Help how to clear the critical diagnostic and they didn't know - but said that it would not prevent from e-filing!  Lots of useful information there.  I do TurboTax for Intuit and 8915 is available in that application, but it sure got missed on Lacerte application this year.  So much for consistency across the applications and developers caring about the Lacerte app.  😞