My LTE works at 3G speed, how can I fix this?

My data used to work at LTE speed with no problem up until that day where Fizz users were out of service from ~20h00 to 3-4 in the morning. I live in Québec so I am unsure of how I do not have coverage for LTE speed.
My phone is set for LTE, but in the corner says it’s at 3G. It doesn’t have to do with bad reception because wherever I am, home, work, on the bus, it stays at 3G. How can I fix this or who do I contact for this issue?
I AM paying for LTE not 3G data.