I left box 52 empty due to an error on a t4, I want to know how this will affect my return. They have already given the refund

Amounts in box 52 of your T4 is transferred to Line 206 on your T1 General. This is then transmitted to CRA, and they use this amount to adjust your RRSP contribution room. It should not affect your tax refund/payable. However, you should still file a T1-Adjustment to report this discrepancy to ensure you have proper RRSP room calculated.

https://turbotax.community.intuit.ca/replies/3404101