Problem accepting family invite

[Felix_64]

Hi,

having terrible trouble accepting an invite from a premium for family account. When I accept it, according to the support page "You’re redirected to a new browser that contains a pre-filled token. Click REDEEM".  This doesn't happen, instead I'm prompted to enter my address, it then says I'm a family member but nowhere do I get a browser window with a pre filled token.  When I click redeem, I try entering the code by hand but just gets rejected. Spent 90 minutes on chat with an agent who couldn't fix the problem. Was told how important it was we were both at the same address, so made sure the post codes matched, but still failed.  I wasn't sure if in my account I had to pay for premium membership before accepting the invite.  I tried this, still no good, just more out of pocket. Anybody any suggestions?