Progression on weapons and vehicles stuck

Hello,

After months of playing, I've recently noticed that my tier progression on various weapons and vehicles seems to be stuck or in an endless loop. The mastery seems to advance, but not the tier - which is forever stuck. And hence no red skin unlock. Most of the weapons I use very often, seem to be stuck.

Weapons that seem stuck:

- PP-29: mastery 21, T3, verified looping kill count

- PKP-BP: mastery 13, T3

- GOL Sniper Magnum: mastery 22, T3, verified looping kill count

- Vehicles that seem stuck:

- M1A5: mastery 39, T2, verified looping kill count

- T28: mastery 38, T2, verified looping kill count

I've check other forum posts and can't seem to find a solution. I am playing on multiplayer and game modes such as breakthrough and conquest close quarters.

I've just spent nearly an hour chatting with EA Help who basically told me they can't help me... A very annoying conversation, and an even more annoying problem.

Any suggestions?