Azure Pipeline - npm install error 403 with Azure Feed
Problem solved. What I had to do was go under into the feed -> settings -> permissions, and add the ...Build Service... as a Contributor.
Microsoft should really add this as part of their documentation. Took me several hours of random attempts before I found it..
This is a different solution for the same message, although, in this case it will fail from any location.
Trying to publish a package version previous to the last one published on the feed will return the 403 Forbidden error to, even if it's not a permissions issue.
Updating the package version to one increment after the current version will solve the problem.