Hi Wale, the property you're looking for is the HostingAgentId, which exsits at Reservation level as documented in Property HostingAgentId | DataMiner Docs.

Additionally, it's possible to add the referred property as Properties list of the Reservation to make it appear under the Booking Properties, which can be added a column of the Bookings table itself.

Kind Regards,
Flávio Jacinto