Restarting my phone did not help.
Device: Moto G4+ (Android)
Best answer by pstonethompson
Do you have any apps that overlay the screen, perhaps one that filters/reduces red light in the evening to help you sleep better? Or ones that modifies colours in some way? These can prevent you tapping on OK.
If this is the case please try pausing that app before attempting to connect using WiFi Security. I believe that you only have to accept this prompt once unless you uninstall/reinstall the app.
After that hopefully you will be able to connect.
If that doesn't help please reach out to our excellent Support team.