In the main menu go to Properties > Tariffs and click into the property
Link BOID - Enter the Back Office ID
Link Owner - Select the Owner from the drop down list in the Owner field
Link Cleaner - Select the Cleaner from the drop down list in the Cleaner field
Click on Save Changes
NB. If the Owner or Cleaner don't show in the dropdown list then use the Add Owner or Add Cleaner button to add these users.