if the above does not fix the problem - look into your T3 (CRA)/RL-16 (QC) forms; I had the same issue and the problem was that there were several separate entries, then what originally looked like a summary (adding all entries) but for me it was a SEPARATE and DUPLICATE form but with some of the fields missing. After confirming that the last entry was indeed an error, I deleted the duplicate T4/RL16 and everything worked. Just filed QC. Good luck.
