How to unlock UCAV air burst in Battlefield 4? I’M DYNAMITE

Hi, I am facing a problem unlocking the UCAV air burst in Battlefield 4. I have completed the assignment “I’M DYNAMITE” requirements. I have done all tasks in one game, but the battle log still shows that I have not unlocked the UCAV air burst. It also says that I have not reached level 20, while I am actually level 124. I have tried restarting the game, logging out and in, and playing on different servers, but nothing works.
I even reached out to EA chat but they told me to post the question here. Does anyone know how to fix this bug or what I am doing wrong? Any help would be appreciated. Thanks.