Last clip not reloading into weapon current ammo VAR

i have a weapon system setup to reload and take ammo pickuped and stored in a backpack structure when reloading its supposed to go to my current ammo in mag in weapon bp but when i do it for the last clip/ammo left it doesnt actually go into the clip and wont fire?

any suggestions?

Make sure that your check for current ammo is either ClipsRemaining >= 1 or ClipsRemaining > 0