"Assign a lab resource" in a Test Cell

Hi all.

I have following question: when I'm trying to create a Test Cell starting from a Test Environment previously defined, it happens that when I click on the "Assign a lab resource for each row" button to instantiate my test cell with the available lab resources known to RQM, RQM assigns lab resources that are already "reserved" from other users, so I'm not able to reserve them for me. And I don't see any option to ask RQM to look for "not reserved" lab resources or to retry the association until finds a free resource.

Where am I wrong? What should be the right way to instantiate a Test Cell?

thanks in advance

piero m.