Runner API not listing all runners

Summary

When accessing the runner API without any parameters we do not see all of the registered runners.

Steps to reproduce

In the browser go to: https://GITLAB_URL/api/v4/runners/all

What is the current bug behavior?

In our case, we expected to see a runner with id:256 which is active and online. However, no runners with an id greater than 206 were listed.

In the Gitlab admin section I can see all of the runners including 256.

What is the expected correct behavior?

We should see all registered runners.

api ~runner