Piece fell off? my front bumper

It is the towing eye bolt cover. It is meant to come off when a tow truck driver uses the screw in tow bolt that is with your spare tire.

 

Above is the answer as to what it is ... don't forget to order the "string" retainer.
Not sure how the cover and retainer fell off... could of had a broken clip from prior removal, yet the missing string is odd, implying someone was "in there" before.

You can search for price, yet I think the part arrives not painted.
That could add to the cost.
As an option, paint or wrap both sides in the color black.

Good luck, easy to install.

 

Item 15 here:

Bumper & Components - Front for 2012 Toyota Prius V | McGeorge Toyota Parts

I don't see mention of the retaining "string" part? And yeah, appears to be unpainted.

 

No separate "string", it's just molded as part of the tow eye cover itself. You can spot it (if you squint, black-on-black) in images that show the cover from behind.



You can see it just has a barbed end on it, you pop it through that tiny rectangular hole you can see down in the corner of the opening in the bumper.

I am not sure that part number/picture is exactly right for your v (the shape of the entire cover seems too square, and the retainer seems to come from the wrong corner) but it gives you the idea.

Is this by any chance an alternate or aftermarket bumper cover?

 

Just a tip: a pen knife blade slipped in the gap is gentler/better than screwdriver, for finessing that thing out. The gap is pretty tight, and screw driver may chew things up.

I dread to think of the tow truck driver's technique, lol.