Waiting for payout

I submited my tax in august 2019. I must get a refund end of september untill now still no payout. I just spoke to a lady in the call center she says there is no turn around time i must wait for my money they are buzy wit tax form 2016. I asked her what has 2016 tax have to do with my refund in 2019. I submit every year in august so why do they only pick up a problem 3 years later. Her reply is sorry sur you have to wait until they pay it out. Why do i have to wait but if we submit late we get a penelty so I WANT INTREST ON THAT MONEY.