I am supposed to repay money through the Home Buyer's Plan, but forgot to repay it in 2017. What should I do? Do I need to enter anything on my 2017 tax return?

If you were required to make a Home Buyers Plan repayment and did not make one, you do not need to report it on your income tax return.  The Canada Revenue Agency will automatically add the amount of your repayment to your income on line 129 of your tax return.

It is better to report it yourself on line 129.  waiting for CRA to adjust can mean a difference between owing and a refund for some people. Entering the info now will give a true picture of what the individual owes or get back. So if haven't already sent your tax go and include it or wait for reassessment as indicated by the moderator.