@BByod thanks for your reply. Unfortunately my partner has not been living in the UK for 15 years and he’s not registered as a voter anymore. He doesn’t have an MP. So, that’s not an option, sadly.
I’ve emailed the Durham upgrade team email address as well but never received any reply from them, not even an auto reply.
I will try emailing Durham again but I’m not sure they will reply. Being overseas is really difficult as we don’t have many options.