Website lost after domain change

We are a medical centre based in the UK. We had a WordPress site created by our previous web designer, to look after our virtual patient group and to act as a forum for patient-doctor discussions.

We had to change web designer/host and, whilst retaining our original domain of https://www.westcourtmedicalcentre.co.uk, we added a new, shorter domain of https://www.westcourt.surgery which now is the main address.

Unfortunately, this change caused our WordPress account to disappear and we seem to have lost our patient group forum! I’ve tried getting in touch with the previous web designer but he says he’s unable to help. PLEASE, help us WordPress! Our patient group members are upset that we’ve lost a valuable communication tool.

The URL is was using to access the site was https://www.westcourtmedicalcentre.co.uk/vpg/wp-login.php?redirect_to=/vpg/

Thank you in advance.