"A business process flow already exists for the target record and could not be created" on SetProcess Workflow

I'm on Dynamics 365 On-Prem. I made a workflow that only does the action SetProcess. When I call this workflow inside my entity and that this business process flow already exist for that entity, I get this error message. I thought SetProcess could be used to switch the current active Business Process Flow and not creating it? Can anyone tell me what's wrong? Searching for this question online only brings old bugs with an old version of CRM.