Wage Theft Canadian Tire

So there is a trend I’ve recently noticed since I started working at this company. You’d be scheduled for 7.5 hours in a day excluding lunch , then you work 8 excluding lunch and they only pay me for 7.5 hours. I see they keep on overriding my punches…Almost every-time when it’s time to go home they will give you stuff to do literally before you walk out the door then when it’s pay time they don’t pay you to stay back. Now a few days ago I wasn’t able to take lunch one day because the shop was so busy. I worked 8.5 hours that day with no lunch and now they override it to 7.5 hours again

Isn’t this illegal ? We don’t even have an HR where I can report this to