extremely high data usage

Hi - I've been trying to get answer to why my data usage has suddently gone up. Over the last 6 years that I've been with Xfinity usage has been between 300 - 500 GB average. Suddenly starting November of 2021 the usage has gone past the 1200+ limit and keep getting warnings as soon as 10 -14 days into cycle that you are 90% of usage

I've called a number of times to no avail and this is frustrating. Just this month on 6th my usage showed around 80GB and suddenly last night it went up to 611 GB which is ridiculous. Can someone look into this and help me