Popping noise when bouncing bed

Any idea where this would be coming it’s a 2020 tundra trd pro with less then 20k on it it’s a distinct popping noise from the rear right side of the truck

 

Mine was doing this. Took it back to the dealer last week they tightened up the U bolts and it's gone

 

I had a similar issue. I searched everywhere and checked bolts. Turns out I had an acorn wedged between the cab and bed. It was making noises when the truck flexed.