404 Errors to AH Endpoint

I’m querying the auction house API and the test query works on the API documentation page with the default values, I’ve taken the working values on the API documentation page for the AH API call and in postman the calls to the US end points work but EU endpoints are just returning thre 404 error.

Any other call to an EU region call returns a 404 error, ‘{“code”:404,“type”:“BLZWEBAPI00000404”,“detail”:“Not Found”}’.

I can get an access token fine and I can query the connected realm end point fine as well, just seems to be the AH end point causing issues.

This is the call I’m using (there is a space in the url after ‘https’ as it wouldn’t allow me to post it otherwise):

https ://eu.api.blizzard.com/data/wow/connected-realm/507/auctions?namespace=dynamic-eu&locale=en_GB&region=euu&access_token=

507 is not a valid European realm ID. I guess they’re globally unique.
Try 509, or fetch a list first from /data/wow/connected-realm/index endpoint