@Chausson Thanks for the additional help. I have eventually managed to get it working using Tetther to add the router and using the WPS button on both. Many thanks for all your suggestions. Very...

@Chausson Thanks Dave The Tether app is not necognizing the extender! I have also tried resetting the extender as well.

Have changed Broadband service provideer and have new router and password. How do I change the password on my One Mesh AC1200 extender. Model No RE215/RE315?