Tuning Slayer 308 won’t cock

I’ve got a Slayer 308 that won’t cock or fire. At first I thought it had a leak, as when I hook it up to the fill tank it makes a hissing noise, but the tank gauge shows 3800 psi.



I’ve emailed Tom and am waiting for his reply, but if anyone has seen this before and knows how to fix this it would be appreciated. Thanks!
 
Tom I have a slayer 357 and I need a user manual for it (it never came with one )

I’ve been trying to reach you via email cell phone and text for months now with no reply?

I just have a couple of simple questions I don’t want to damage the gun, I promise I won’t take up more than a couple of minutes of your time I just need some simple advice like what pallets to use and what is the maximum air pressure to fill the air rifle.. please reply to me.

PS if anyone else can assist I would be forever grateful

thank you and happy holidays