Wifi disconnection

Hello all. For about the past 2 months my modem/router has lost connection/restarted itself every night. The problem has gotten progressively worse as now it does it between 5-10 times a night sometimes. I contacted XFinity who advised they are not having any issues on their end or in my area. I’m curious if this is related to my modem/router? Sometimes when the modem loses connection it will reconnect within a minute or quicker. Sometimes when it restarts, it will erase my set usernames and passwords I have set for my wifi and force me to rename both the 2.4/5.0g channels and their passwords. Hoping to resolve the issue as it’s made using wifi at night impossible.