I have a Samsung Galaxy S21 Ultra.
Whenever I return to my apartment building, it first encounters the building-wide public wifi network and tries to connect to it. This network requires sign-in so it never does actually connect. It keeps using cellular data.
Then I get to my apartment which has a secure and fast wifi network that it already has the password for... And it's still half connected to the public network, waiting for me to sign in.
Hours later, I'll realize the connection seems slow on my phone, notice the problem, and then switch the wifi network.
This is incredibly frustrating because this is much dumber than a smartphone should be (a known good network is sitting right there and it's not using it!), as well as causing me to use much more of my data plan than I should need.
I've tried telling it to forget the network. I've even turned off auto reconnect for the network. Which it helpfully shows to be turned off even while it is actively trying to do just that.
Solved! Go to Solution.
So... I ended up resetting network settings and that fixed it.
I tried turning various settings back on (including "turn on WiFi and Bluetooth automatically"), and couldn't get it to happen again.
I'm just hoping that it won't come back, if/when I actually do need to connect to that network again.
If it happens again, try this
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