I am still having this issue. Everything from my T4 is entered correctly and it's still showing the exact amount that I paid to CPP as an overpayment. I called and customer service couldn't help me

you need to input the cpp pensionable earnings from your t4, then cpp wont show as an overpayment,  I had that issue also. box 26 on T4

I already did that and it didn't fix.

@JessicaBlank03 Please try deleting the T4 and re-entering it.

Thanks! It's corrected now!

@JessicaBlank03 You're welcome! 

Yes, that issue has ben fixed. Thanks for your patience,

I have entered the CPP deduction from my T4 and it is showing as an overpayment on my tax summary.  It is only showing the EI deduction.

That was the problem - they didn't have an amount in box 26 - thank you

I am filing my wife and my taxes jointly on turbotax.  I filled in my wife's T4 info including $3052 in CPP deductions. In the tax summary it doesn't show a CPP deduction it shows a CPP overpayment of $3052. My wife retired a couple of years ago and receives a pension but she went back to work and paid CPP. My concern is that we will owe more in tax if this overpayment is reversed and/or also that if her CPP contributions aren't valid then it will reduce her CPP when she does retire.  Why did this happen

Put in the pensionable earnings. Problem solved