Tim Hortons employee tried to keep change

Went through the drive thru. Bought a xl coffee 2.45 handed over a $5.00. Employee handed me coffee then closed window. I waited. Employee came back after a few minutes and states ..yes do you need something? I state yes..my change..Employee oh I thought it was a tip...calls manager over to open cash..tells manager I want my tip back..

I look at the manager and tell her I didn't leave a tip..the Employee kept the change on their own. In a huff she gives me my change..

Guess I'm going to buy coffee at McDonald's ..