Legality question regarding telus phone bill/termination?

So I pay my bill every time I get a bill. Often it seems I either get it late by a month or 2 which doesn't bother me much because a high bill with interest is whatever as money is no object for me.

because it had been about 2-3 months since my pervious bill I dumped some money on my account which would more than cover the cost of a couple months. I have a total limit of 200$ on it and once when I was about 40$ away from that limit I got a text, so I paid it so I didn't get terminated.

So again, I dumped that money on last month but today I got a notice of termination if I do not pay 67$. I still technically have not got a bill and 66$ is high for a month of service plus taking into account I probably over paid last month its not possible.

I have a phone from 1995, no internet or anything.. it is a phone. My bills should be 43$ after all the service charges, etc... 30$ no contract month to month plan.

I use my phone for work.

If they terminate or demand I pay without seeing a bill, do I have legal ground to sue?