Do I *have* to read my SaskPower meter??

My husband and I just moved to Regina iand we've never had to pay utilities except power when we lived in BC. The power bill came every 3 months and we didn't have to do anything for it. I'm just noticing now on my SaskPower bill that they use an "estimated" number for our power usage, resulting in a fairly low bill. I didn't know we had to submit our own readings every month. The reminders to submit our reading ended up in my junk box on my email.

Do I have to actually read and submit our meter readings?? What happens if I don't do this? Just wondering because I'm super confused 🙃