Thanks for taking the time to post in regards to upgrading but the problems with the password. We appreciate you raising this via the forums and welcome back!
We aren't able to change this for you from here, when you call in and speak to the team if you're the account holder and can't remember the characters requested they have the option to ask additional security questions. Once completed they can then reset the password for you. Alternatively they can arrange for a letter to be sent out with a password reminder. The best number to call would be 150 or 0345 454 1111, what upgrades were you looking to make?