I have error code 2123 for an overpayment or EI. How can I delete it from line450 on my 2014 return? I can't seem to modify line 11 either.

I am unable to NETFILE as I received an error Code 2123, telling me that I am past the period to collect for an EI overpayment and that line 450 must be deleted. I cannot override it, or lines 11 or 12. I need to NETFILE as I cannot make the deadline the CRA set for me if I use snail mail or even courier. How can I override this amount?