wi fi - My phone stopped remembering wifi passwords!

For some reason that completely escaped me, this here Samsung S3 mini stopped connecting automatically to my home network, always requiring me to re-type the wifi password.

Since then, I noticed that it's not just for my home network, but for all wifi networks.

More concretely, here's a sample of what happens:

• I try to connect to a WPA-protected wifi.


• Android asks for the password.


• After I provide it, the phone connects successfully.


• I turn off the wifi (on the phone).


• I turn it back on.


• The phone doesn't auto-connect to the wifi.


• I explicitly select the wifi network to connect to.


• Android again asks for the password I typed in a minute earlier.

Any idea how that can happen? What could I have done to deserve this? What could I do to redeem myself and fix this problem?

More details: "forget"thing ("disconnect"ing from) the network explicitly makes no difference (it still doesn't remember the password next time around), rebooting the phone neither. This phone is running Android-4.4.2, is not rooted.