If I remember correctly when LORTV changed to MAVTV Plus you had to change your LORTV password to a new MAV password to access the MAVTV+ platform. I don't know if this is of any help.
I did encounter a few subscription / log in issues around the time of the rebranding but had no issues with the contact us form, swift reply, and issues resolved. Hopefully, you'll be sorted soon enough.