Basic t v keeps locking up

Xfinity basic t v keeps locking up. I have to press the button and I am missing important details in the things i'm watching on t v. I have numerous numbers of times reached out to xfinity.They have sent technicians to the house. No one seems to be helping or resolving the issue. A keep complaining , and nobody seems to help. I guess the only thing I can do is cancel my service.