This looks like a PPS parking charge (not a
pcn
like a council would issue). In effect it is just an invoice & unenforceable as issued on private land. They then send you 'debt collection' letters to worry you into paying up (there is NO debt in the first place).
Your 'FINAL DEMAND' letter looks like a joke, IT SAYS 'Dear Sir/Madam'..!!!
How are they going to take you to court if they don't even know your name????
This is a well known parking scam originating from private land such as shop car parks and alley ways behind shops/warehouses etc...
If you get a letter or ticket that isn't issued by a council (PCN) or police/traffic warden (PCN or FPN) then it is most likely a PPS 'invoice'. The best you can do is ignore all letters and DO NOT WRITE TO THEM. You could write and complain to the land owner.
If you get clamped or towed by a PPS then you should pay by credit card under protest, to get your car released and then you can put a claim in with your credit card company or if you paid by cash you need to go to small claims court and issue proceedings against the PPS and land owner.
There are parking help forums if you search for them on google.
Good Luck.