Boneyard VFC FNX45

Here is my VFC FNX45 which I have had since 2020 covid and was bought second hand. Absolutely love this pistol but been having issues with feed, slide not fully cycling and venting gas. I have bought a new spring for the barrel to hopup and new nozzle returned spring in attempt to fix it up however no such luck. I have since moved onto a co2 glock so this have been left to the side.  Did fit a new maple leaf rubber (i honestly can't remember which one) which has seen a couple hundreds of rounds before having issues.  I believe all 3 mags are leak free, they have small amount of gas in them and seems to be holding. Unfortunately I can't test these to full gas fill as I don't have any green gas.  Obviously this has been very much well used as you can see by the photos, was my only pistol for the last 4 years and has seen many many bbs through.  Looking for £105 all in posted. Offers are always welcome.