While you don't show the vintage of your trailer, can assume that it's an electric awning.
If that piece of plastic is black and came from the front awning arm, it's most likely a cover for the wiring. Ours came off in Virginia along I-81 but I was able to retrieve it
As far as creep, one end of the roller springs may have 'lost' tension by popping out of the retainer or even broken. Not a fun repair.
If the trailer has a manual awning, the locking lever pawl may have failed in which case you can try to find a replacement or do a net search for an awning lock:
https://duckduckgo.com/?t=ffsb&q=RV+...ages&ia=images.