iPad mini not connecting to wifi

My iPad mini wont connect to home WiFi. Other devices do. I have reset network settings, and followed all other suggestions I could find. In Settings->WiFi the network shows up, I choose it, it shows the check mark next to it, the WiFi connection shows up on top of screen for a fraction of a second, then it disappears again. So Settings looks good, but there’s no connection.

This started once in a while, but I could always reset it, but it got worse until now I can’t connect at all. Any suggestions?