Blowback not working properly

[Ftwizard]

Hi, first post and it’s about a problem I have with a WE XDM-40 pistol. The first shot works as it should, but the second just fires the BB, with no blowback. 

Any ideas what could be the problem?

 

[HELIflipper03]

Have a look at the nozzle. If it is cracked or broken it could be leaking gas in the wrong direction, therefore not having enough gas to cycle the slide. Also check that every seal is well lubricated and are not damaged.