Data issues!

I called Xfinity last week which did not go well and, as usual, had to call Corporate. Corporate used to be helpful and I could talk to a human in the USA but not  so anymore!!! I end up wasting an hour of my day just trying to call Xfinity. They gave me a case number and told me I would be called back the same day. That was not so! I used to get a call within 24 hrs. I have tried to call back every day. Twice, they said the data usage was exceeded when nothing has changed in decades. The data in the house usually is around half of the 1.2. Then, suddenly, data issues in Jan. I called and they said you get one free but could not help as to why when nothing is different. The next month the data was back to half as usual. This monrh I get a message in mid March saying 75 percent of data had been used. Then, in a matter of 48 hours I blew over 1.2. This is not possible!! There is no downloading, no gaming, nothing out of the ordinary. I'm am still trying to get help. They did the same thing to my sister in Nov and Jan. Is this just a ploy to get people to pay 30 dollars more for unlimited data. As a many decades long customer, I have had it. There is absolutely zero customer service and the [Edited: "Language"] you do get could drive you to insanity trying to get it. What has happened to Comcast!!

[Edited: "Personal Information"]