Definitely a problem with turbotax program. I spoke with CRA agent & was very helpful in providing explanation of forms, etc.

@drewsj2 Make sure information on the T4 slip is properly entered. We also suggest do it in form mode directly, compare the amount in box 16 and line 44800, and then check schedule 8 to get a look at the calculation

Please refer to these links for more information: CPP contribution rates, maximums and exemptions

Contributions to the Québec Pension Plan

I'm having this same issue. 

My CPP payment was 3,867.80 (so a $0.30) overpayment

and CPP2 $188

Yet, on line 44800 TurboTax is saying I have an overpayment of $4056.00 (rounded).

@mamoon On your T4 slip, you entered CPP contributions in boxes 16 or 16A, but you should have an amount of pensionable earnings in box 26. This box is required.

If box 26 on your T4 has zero ($0) in it, you don't have to do any changes, just enter zero ($0) as required. If box 26 is blank, enter the amount from your box 14 (up to a max of $73,200).

Thank you for choosing TurboTax.