This is a general restriction: when using a single request to deliver multiple changes to the same item they must be sequential. Find below and example of how to reprouce this message: For example:
COR0005191E Error: Format ECL-12901600920 is not allowed for Item type EGL:PROJECT This is in spite of the fact that ECL is already related to item type PROJECT. This functionality worked in version 10.1.3.
Running the command “SWS <Product:Workset Id> /PARALLEL_EXTRACT” from the DMCLI, Customer was then able to checkout a file that was already checked out. Command-Line reference guide, page 335.
Deploy request finds all items related as IRT to the specified request and all of its child requests and deploys these items to the specified stage in the context of the current project. So all items related IRT to an already deployed request would have to have been deployed to that stage already .
When attempting to action an item (s), the following error can occur: COR0005355E Error: You are not allowed to action this Item as it is currently locked