Hi,
Please check that the PR release strategy has been changed or introduced in the middle,
Thus whenever you were going to Transaction ME54N, it will throw the message that "Purchase requisition xxxxxx cannot be release" check that PR no, is it old or new?
This is because you have changed the Release strategy and previous PR has not been
triggered for your new strategy until you change something in that old PR,
Thus it will go to the Display mode when you enter ME54N,once you hit the change button and change something, then the new release strategy will get triggered,
In case of newly PR created with multiple cost center after customization of Release strategy I think you will not get any hindrance, just try and share
Check note 493900 - FAQ: Release Strategy -question no 10
Thanks