You'll see the following error message in H&R Block’s 2017 tax software if you chose to both stop and restart your CPP contributions on self-employment earnings in the same year:

You can’t choose to stop contributing to the CPP and choose to restart your CPP contributions in the same year. You need to choose one option or the other. Please review the information you entered in the second part of the form. [error code: 127] 

How do I fix this?

To correct the error, return to the CPP/QPP page and select a month in which you would like to either stop CPP contributions or restart CPP contributions; not both. You can only complete this form once in a calendar year. If you choose to stop CPP contributions in 2017, you have to wait until 2018 to restart your CPP contributions.

Note: You can find the CPP/QPP page under the OTHER icon on the PREPARE tab.