Router was reset to many times to remember. The password has always contained onbly numbers. Very frustrating that you only can connect by changing your router security, I won't be trying that.
If you are not prepared to try different things then you will forever be frustrated.
First of all you could see if you can connect without any security. (Just as a test)
You could then try WPA (as a test)
You could also try a different password containing letters and numbers (as a test)