Internal Server Error when uploading to conan

Version: Self-Managed 12.10-ee Ultimate Trial

I am trying to evaluate the built-in conan registry but whenever I push packages using conan upload I get Internal Server Error messages when it tries to upload the conanfile/manifest

I am using the helm chart deployment of gitlab, if that matters
I have double checked all of the credentials and URLs

exactly what I am doing (GitLab CI):
package:
stage: package
image: conanio/clang9
before_script:
- conan remote add gitlab https://{{INSTANCE_URL}}/api/v4/packages/conan
- conan user gitlab-ci-token -r gitlab -p “${CI_JOB_TOKEN}”
script:
- conan create . {{PATH}}/stable --build missing
- conan upload {{LIBNAME}}/1.0.0@{{PATH}}/stable --all --remote=gitlab

I have removed the specifics for privacy.
For the PATH, I just took the URL after the instance hostname and replaced / with +, as it says in the tutorial.

This doesn’t work on CI nor my local machine.

The production logs and object storage logs in k8s do not show anything unusual.