GregoryMcCormick owes me 1.1b OSRS (TBOW)

Scammer's profile link: @GregoryMcCormick
Explanation of the trade: I paid him £600 to purchase a TBOW from him on 4th may 2020 via paypal, the transaction took a good few days to go thru on gregorys behalf, once it did he told me he was on lockdown so he would be let me know when he could trade me, over the last few weeks he has told me hed trade me that night but never did, or told me he was gettin GP from his cousin to trade me and didnt get back to me, when I messaged him on disc he asked me who I was.
Amount scammed: £600
How they scammed:He has not delivered the item or I would accept GP for it, and has blocked me on discord (Imgur) And isnt replying on sythe in the last week even tho I've seen him online.
Proof that it's their Discord:I gave him my disc via pm and he sent me an inv but has now deleted messages where he told me who he was but I do have all other chats saved Imgur
Discord ID + Unique Discord ID: His username always changes everyday, right now its (Mystery12#5380) 269488396437553163-Unique
Other relevant trade screenshots: redacted - sensitive info