i have WiFi issues also. I have a regular s20 5g (sm-g981u1). my router is a smart rg sr 16ac. Crazy thing is that it knocks my laptop wifi off too. When I turn phone wifi off laptop internet comes right back. They both have independent connections to router and do not share wifi in any way. I read that it may be a mac address issue that you need to assign for the phone in the router but my ISP has my router administrator page locked down. waiting to contact them.
I've been dealing with this problem for months now since I got the s20+,
and have done all the requested attempts of rebooting phone, wifi, etc and nothing worked. I think I just figured out the problem as my phone had been working and not dropping the internet anymore. I found it by accident. Pull down the the screen to access the settings and select power mode. Uncheck limit CPU to 70% and accept. I'm sure it'll decrease the life of my charge, but so much better than constantly getting booted off my wifi, not to mention at work where I rely on being on wifi. FINALLY!! I hope this works for others and that's why I had to share!!
Here is how to fix the problem where WiFi keeps turning off automatically. Fix this annoying issue and get your smartphone working as it should normally.
