Curious, did you perhaps take the .conf for nginx from one of my posts? Because youre using one of my servernames/domain in the .conf and that wont work for you since its internal to me only.
Are you trying to self host the multitenant activitypub project pulled down from their github as a server or bounce yours off of the Ghost platform one?
It looks like you have a LOT going on here that is tough to decipher, and probably needs a bit of a fresh start, you curiously have a location block in your ssl.conf…
edit: Yeah, it looks like you pulled that from this post Self hosted Ghost 6 on Raspberry Pi 5 via Cloudflare Tunnel: ActivityPub routes (.well-known, /.ghost/activitypub) failing with 403 - #4 by disgustipated
That block i pasted there was meant for that persons situation, the reference to “ghostactivitypub.rabbithole” needs to be replaced with the server name of the activitypub server if you are running it locally. the person on that thread was running the whole activitypub project on a server like myself, I believe most people self hosting ghost use the ghost provided activitypub server which i think its ap.ghost.org. someone else that is running that will need to help if youre not using the activitypub server from the ghost activitypub github as im not familiar with it. you do have some concerning things in your conf files though.