Why I can't use soldier vehicle until about a minute?!

HELLO

when i want to use some vehicles like Ucav,mortar,mav.... those small vehicle that have a small screen remote control to control them i can't use it,i have to wait about a minute until the vehicle appear and i can deploy it the vehicle is invisible i can see just the screen remote control after a minute the main vehicle appear and i can deploy it.

EA advisor said delete the game(battlefield 4)then download it again,i did that but didn't fix that issue.

*SORRY FOR MY ENGLISH I'AM NOT ENGLISH PERSON.