Ammunition vendor is buggy

Since today I can use to “refill ammo” unlimited times on the vendor machines.
The first time it costs normal like about ~2k (I'm level 27 Moze) and then I still have the option to refill for 140 . I can spend 140$ each time and get nothing more because I’m full on Ammo. So it is a great way to burn $$$ but I think this is not what it should do.
As mentioned, I had no issues yesterday. If I once refilled my ammo the refill button would disappear.