The game automatically changes weapon modules after removing the muzzle

If I use all 100 attachment points on a weapon but need to remove the muzzle, the game automatically returns the muzzle and removes my last attachment after EVERY match.

For example, the M4a1 has 90 attachment points (including the muzzle). 
I want to equip a green 50mv laser for 20 points. To do this, I remove the muzzle for 10 points and equip the laser.
That's it, 100/100 points are used.

The game simply returns the muzzle and removes my laser after each match.

We have tested this problem with 2 friends with different weapons. Result was the same. Game change attachments automatically for returning muzzle after every match (or before it).