BT extender won’t connect with full fibre

[#1]

Hello, new to this forum. I have just had full fibre installed replacing Plusnet fibre plus. I realise now that my BT DUAL WI-FI extender won’t connect. Contacting Plusnet did not resolve anything as the operator could only suggest I do my own research. I no longer have a lap top to connect to and am now unsure whether to buy another extender or not . If I do how do I know which one to buy? Plusnet could not tell me anything about the technology and compatibility. My previous system worked well for me so am now kicking myself for accepting the offer of faster speed. I also lost the landline! Any help would be appreciated.

[#2]

When I recently recontracted on FTCC I got a new HUB 2 router. I set it up and changed the SSID and wifi password to that I had previously used on my HUB 1 so that laptops, phones etc could easily use it.. I have a pretty basic BT extender ( it only works on the 2.4GHz band) and found that it would not connect initially. I switched it off and left it for a few minutes before switching it back on. When I then attempted to connect to it via my laptop I had to renter the wifi password but it did reconnect and is still working some few weeks later.

Therefore maybe you only need to reboot the extender and renter the password etc. I cannot see that FTTP itself should have anything to do with the extender not working as long as it recognises your router / SSID.