one
The user did enter the wrong WiFi password, so it will prompt the password error, you can enter the phone's Settings - wireless LAN - to find the WiFi signal, click to see the details, and then click ignore this network, ignore the correct connection can be.
two
There may be a problem with the network Settings of the mobile phone leading to the error prompt. You can enter the Settings of the mobile phone - restore - restore the network Settings, and then turn on the wireless LAN again, search for WiFi signals, and re-enter the correct password to connect.
three
It may also be that there is a problem with the Settings of the router leading to the error on the mobile phone. You can restart the router to solve the problem, or restore the router to factory Settings and then reset the network parameters to solve the problem. If necessary, you can change the router to re-establish the WiFi signal to the phone connection.