Keg problem - liquid post is stuck and doesn’t come back, so no pressure in the keg. How to fix it?

[Omega]

Hi, there, I bought this keg and never used it, but it looks like it already broke - the pin inside the post sunk and does not come back releasing gas. Could advise me how to fix it? I guess it is easy to remove it, but do I need to order new new post and replace it?
Also, the reason why I did not use it before is because I don’t need it. I wonder if I should sell it. If I do then should I sell it with a broken post or fix it first? Thinking to fix it first to increase the number of people willing to buy it unless it is too expensive to fix it
Thanks

 

[Rodcx500z]

Take it out and clean it, prob got some grud in it

 

[RichardM]

You can remove the post and disassemble it for cleaning.
If needed you can replace the poppet and 'o' rings.
https://brewkegtap.co.uk/products/universal-poppet-pair

 

[SMP Brewery]

Probably as Rod says just got something in it just needs a clean, I would however get a PRV for it, you might want to invest in a new lid.