WP Booking System in Bellevue / Themeforest can no longer update booking


I have a simple Wordpress 5.5 website www.montevella.com, that has been running for several years.

Earlier this year the administrator interface for the ncluded / free WP Booking System became slightly corrupted. Before there a table for each room per month with date / booked status / comment. Then several months ago, this nice table format was replaced by a list of date followed by every comment that was ever entered in the past few years , followed by the booking status. A bit messy but you could update the bookings.

Now in the past week or so, I can no longer update any bookings;

The versions are:
Wordpress 5.5
php 7.0
WP Booking System

There has been a notification since March… " You have not set your Meta Box licence key yet, which means you are missing out on automatic updates and support! Please enter your licence key or get a new one here."

I assume that this was part of the Bellevue theme, but cannot see a way to get a licence without paying an annual fee, and I’m not even sure if this has anything to do with the WP Booking System problem;

Any suggestions would be welcome, as my out of date calendar is causing problems with clients and I will need to delete the booking system shortly if I cannot find a solution