Internet connection doesn’t stay connected

Hi there, I’ve been having issues for months now with the connection in my home. I’ve done nothing new. I have Ethernet cord from my router and multiple time during the day it goes unconnected. Playing video games I barley can get a connection to play online and when I do I can’t complete a game because the connection goes out. I’ve tried to reconnect everything, I restart the modem, I restart my devices I’m trying to get connection on, I’ve done basically everything you can think of. I don’t know what else I need to do. Should I go ahead and buy my own router rather then the one from you? My service next month will 3 years.