Have to keep restarting my modem for every few hours to get internet

i have been having this problem for more than 2 months now. Initially I thought it’s my net gear modem so I was kept on restarting whenever the issue came and that would fix. One day I got fed up with this also 1TB limit plan so I upgraded my plan to unlimited with their own Xfi Modem. Hooked in last week it was fine until few days ago where I have to keep restarting the modem for every two hours or so to get the internet back. I am looking for a serious troubleshooting here not the usual from service teams to restart drill here. Or else I am going ATT they are offering to pay for the termination fee as well.