Looks like the last place that did your oil change didn't put any or all of the bolts back onto your undercarriage cover. I had a car tune up at a Toyota dealership, took a three hour drive, found out that one of my covers was dragging for three hours and disentergrated. I didn't know it was dragging and thought it was just bad wind noise. I called the dealership and showed up with the damage cover and they replaced it for free. Your's doesn't look damage, looks like it just needs the bolts to bolt it back on. Hope this helps for you
Yup, if you got your oil changed at a shop, its pretty much guaranteed they messed up putting the plastic back on. One of several reasons why I'll never let a shop do mine. You can order a new one from Toyota, or try your luck with junkyards. Its a bit pricey to order, I hear.