Rear flap lock

After I took off the panel, I noticed that the plastic panel of the rear flap lock was loose / loose, in principle was off. I then removed the plastic and built everything together again. Unfortunately, it still claps and it definitely comes out of this area. I found it lying in the trunk during a test drive… Did this panel have a function or can you put it away? Is it possible that the disguise is completely gone? VG Bird