WiFi connection doesn't work

Hi everyone, i recently changed my wifi password but i can’t reconnect my WLED devices. To reconnect them i restarted them, i connected my phone to the WLED-AP and entered the new password in “Wifi Settings” leaving the IP set to DHCP but they don’t connect, the page reloads and returns to the home page with the WLED-AP on. I also turned off the 5ghz band on my router but nothing changed. Do I need to reflash my devices or are there things i can try to fix? Thank you!

(i used google translator)