I am having this same issue on namehero server with Event Manager plugin.
Events Manager is trying to update your database, but the following error occured:
FUNCTION broomfie_wp92.RANDOM_BYTES does not exist
It might be that reloading this page one or more times may complete the process, if you have a large number of bookings in your database. Alternatively, you can run one of these two queries directly into your WP database:
UPDATE wph1_em_bookings SET booking_uuid= LOWER(CONCAT( HEX(RANDOM_BYTES(4)), '', HEX(RANDOM_BYTES(2)), '4', SUBSTR(HEX(RANDOM_BYTES(2)), 2, 3), '', HEX(FLOOR(ASCII(RANDOM_BYTES(1)) / 64) + 8), SUBSTR(HEX(RANDOM_BYTES(2)), 2, 3), '', hex(RANDOM_BYTES(6)) ))
OR
UPDATE wph1_em_tickets_bookings SET ticket_uuid= UUID()
And the 1st SQL update fails since the function does not exist and the 2nd SQL update gives 0 records updated.
Please help!