Queuing on Self Hosted Runners for Machine Hardware

How do I enable queuing on my projects that use custom resources against self-hosted runners in CircleCI?

Currently, if two jobs requiring the same self-hosted runner are started the second job returns the following:
Failing job due to no available hardware runner resources for resource class:

I would like the job to simply wait until that resource becomes available.

Can you provide more details regarding your configuration as job queuing is a standard feature of self-hosted runners. For my environment, I use machine-based runners and just caused a pipeline job to queue up behind an active pipeline job without any issues.

It will also be worth you raising a support ticket as the team will provide help even if you are using the free offering, it is just that it will take longer to get a reply. One issue is that the exact text of the error message does not seem to be found in any of the Google indexed areas of the documentation, so it may be an issue only known to the internal teams.