R3090

A SequenceFlow cannot have its source or target in different Processes.

BPMN Process represent independent flows. Therefore a sequence cannot start in a Process and end in another Process, or have any part of its sequence in another Process.

If you have a sequence that is part of more than one Process, you should consider regrouping the lanes into one Process if you want to represent a unique flow, or use MessageFlows to communicate between the two Processes.