The process model ran successfully and completed with the end node.But while checking the monitoring mode we find the process to be Interrupted by exceptionInside the process model we see the process details which is as follows:
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Are there any activities in the process that are still active even after the flow reaches the end node? A process does not complete unless both (1) the flow reaches an end node and (2) there are no active activities. Also, you mentioned that all the nodes are chained - are you sure that is necessary? Generally chaining is only used when the activities are bundled and should all complete before returning information to the user.
Can you provide a little more information about your use case and process model? Some screenshots would be helpful too.
It's highly probable that you had a node still active upon the process reaching the end node. If this happens consistently, the first culprit that springs to my mind is a quick task. When a quick task is assigned, another is immediately generated and waiting to be assigned. If it never is, and you don't configure your End Node to Terminate, then the process will remain in a state of Limbo until this error happens.
By chance, is there any justifiable reason why you can not configure the End Node in question to Terminate? It's best practice to always do so unless there is a strong reason not to. It's also best practice for all process models to have at least one Terminate.