Find your MP’s contact information here. Write them a letter about this issue, mentioning that you are one of their constituents. Below is a sample.
Canada’s new government made a clear commitment during the 2015 election, and again during the Speech from the Throne, to make sure that every vote counts in the next election. This is an incredible opportunity to improve Canadian democracy -- making it more inclusive, representative, and fair.
In order for those ideals to be met, we have to ensure that any new electoral system embodies the principles of proportional representation. As your constituent, I am asking that you work within your own party to ensure that legislation to ensure a proportional electoral system is brought forward and enacted as soon as possible.
[Your Name & Contact Info]