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There are available resources but my jobs are not running, with QOSMaxJobs given as the reason in squeue output.
Solution
QOSMaxJobs appears when there There is a limit on the number of jobs that can concurrently run per user, and you will see that some jobs (up to this limit) do not have this reason while the rest do. Once those jobs complete, the next will be allowed to runany user can run concurrently. If you have submitted jobs that go beyond this limit, they will be marked with QOSMaxJobs. Jobs marked with QOSMaxJobs will be launched when you have completed some of your currently running jobs.
For projects who have used more than their allocation there are stricter limits in place for the running of jobs. This is in addition to the lowering of priority when projects use up 100% of their allocation.