"fails to cycle"

My FN 5.7x28mm carbine keeps failing to cycle and I have to manually eject the casing. It worked fine for hundreds of shots (using SS190 ammo) but now this happens after every single shot. It is cleaned and lubricated. Any advice?

I assume it isn’t damaged right? Maybe you just have a bad case of RNG at the moment.

IS it the same ss109? Or are you using different ammo now?

It is the same ammo, and it shows no damage.

You’re sure it isn’t SB193? The subsonic version may lack the recoil to autocycle.