Ok, now sorry if i get this wrong but is it the skirting which runs along the length of the car under the door? Well whatever its called it has become loose and im trying wo work out a way in which i can attach it on again properly.

This is what i mean (from an underside view). As im sure you can see there are little clips which im sure logic would state should attach to something but they dont, the bottom bit is really loose when the other side (passenger side) is rather firm.
Now my question is this really - is there something i can use to clip/glue/whatever this piece of plastic to my car?
Thanks in advance!

This is what i mean (from an underside view). As im sure you can see there are little clips which im sure logic would state should attach to something but they dont, the bottom bit is really loose when the other side (passenger side) is rather firm.
Now my question is this really - is there something i can use to clip/glue/whatever this piece of plastic to my car?
Thanks in advance!