Wifi Extender requires different password to router

Thank you for trying to help. I had already tried factory reset but the same problem occured each time in that when I tried to connect to my extender wifi, the router password was not recognised. This is a known issue with Plusnet routers and extenders. However, I have now invested in a different brand/more current extender, which had the same issue with not recognising the Plusnet router's password. This time I was able to find someone (via the extender brand's tech support) that understood the issue and they pointed me in the right direction whereby I was able to set the extender password to that of my router - and bingo, works even better than expected.