Hi! I'm having the same issue and for me it's been a little tricky to use JWT. I use this https://jwt.io/ to check the structure of the JWT but it seems like the weatherkit is not working rn. What I did with the p8 file was to create the .pem and it worked a few months ago but today when I tried to use it again I only get 401 responses. I can't check if I have an error or if it is just the API not working.

I thought it was a problem with the security token but everything seems fine. I keep getting the 401 response tho.