Can't connect to wifi and internet is very weak using cellular data
Last week, my iphone 8 stopped being able to connect to the internet, both over wifi and data. I tried everything, multiple times--resetting my router, restarting the phone, resetting network settings, even popping out the sim card and popping it back in. I could still make/receive calls and texts, but none of my apps would update. This will happen even when I'm outside, not connected to wifi, but with full bars.
And when I am home, one weird thing I noticed was that whenever I restart my phone, the wifi icon at the top left corner would flash on for a second and then disappear again. According to my settings, I AM connected, but it's not actually working, and the wifi icon isn't there.
A couple of really bad storms had blown through the area, so I thought maybe a cell tower had been damaged, and I should give it some time. It started working again very randomly about 2 days later, and everything was fine for several days, but now it's happening again. Can you recommend any other fixes?