Unstable Internet (wifi and ethernet)

My speeds are great but I keep having issues of wifi dropping throught the day doesn't matter what I'm doing. If it's on ethernet it drops if it's on wifi it drops. Xfinity app says everything is fine but it's not. It's getting so bad to a point that I wanna leave Xfinty.
I have tighted up the coax cables inside and out. I have done restarts many time. This problem is drving me crazy. I have tried looking for many solutions