Why was a booking placed on the sandbox when rooms are still available?
If rooms are still available, but a new booking was placed on the sandbox, no room in the booked category was consecutive available at the time of the booking import.
Since all booking portals work with availabilities per category, in the example shown (insofar as both rooms belong to the same category) there would be an availability of "1" on all days. Eg a reservation would be possible from the 4th to the 8th.
Since 3RPMS® should not separate rooms (move), the booking is placed on the sandbox, marked there in red and at the same time marked with a hint in the reservation list:
Move the existing bookings to ensure continuous availability and then drag the booking from the sandbox to the room that is now continuously available:
alternative: separate the new booking on the sandbox (with the "scissor"-tool) and divide the booking into the two rooms: