passwords

I've run out of space to store Wifi passwords. I once knew how to delete obsolete ones, thereby freeing up some space. I no longer remember how to do that, and also don't remember where I put the note that wasn't supposed to let me forget! Can anyone enlighten me? I promise I'll have it...

My phone keeps asking for my password instead of letting me use fingerprint recognition to unlock my phone. Here is the exact message I am receiving: "Enter password instead of using fingerprint recognition after restarting device to protect fingerprints" I get this message inconsistently...