This is Duster's famous problem. The gas tank, opening in its entirety, pierce the rear wing. The only way to protect the wing is to limit the amplitude of opening the luchka.
There must be a normal restriction on the cap of the petrol tank, but it is often lost because of its poor attachment. It can be secured on sealant or glue. The part number for this catalog is 78837767655R (the emphasis is on the gas tank).
