Great question!
If you have started a new job with a new employer in a fiscal year, your CPP (Canadian Pension Plan) and EI (Employment Insurance) contributions reset.
You will continue to see those deductions on your paystubs for the rest of the fiscal year.
However, when you file your year-end tax return, overpayment will be resolved as you can claim a refund for any excess contributions made.
Please read more on this subject here.