C4 sticks to the surface even if they were released into the sky

on multiple occasions, im not able to throw c4 on armor vehicles at all.

Ive attempted it 3-4 times in different games, when im able to get to a real enemy player armor.

That it does the animation but wont throw. Once the vehicle in question attempts to drive away the c4 gets thrown.

Leading to my death all the time..