@luksus, When the phone go to sleep, a password inputbox appears. If I enter the wifi password, the phone stay connected in sleep mode, but if I activate the phone and wait the next sleep, the same password inputbox appears.
If the wifi is lost, I must go to the wifi list and clic in the network name for activate the connexion.

@luksus I have only wipe userdata with TWRP, the wipe option from the installer does not work for me.