Proper handling of QCD

Our 2020 federal tax filing includes QCD information on form 1040 lines 4a and 4b as per instructions at https://www.irs.gov/pub/irs-pdf/i1040gi.pdf. Nonetheless we received a CP2000 letter claiming failure to report taxable income in the amount of that QCD. This was eventually cleared by us mailing copies of the checks and acknowledgements of receipt by the charities. In clearing the problem the IRS said “you would have to check with H&R Block (the software we used) as to how this should be put into their software”. But as far as we can tell their software does exactly what the IRS requires already. How do we assure QCD reporting problems don’t recur? Thanks for your help.