Issue with JOIN query...too slow

This join query is extremely slow:

Select OP.* from DPE-WorkflowsAndMessages-INT OP JOIN DPE-WorkflowsAndMessages-INT WF ON OP.workflowId = META(WF).id where OP.type = ‘AkvOpenItemDao’ AND WF.type = ‘WorkflowDao’ and OP.userId = ‘5b96fdb4-8f15-4452-a98a-be1fe3a4435b’ and (OP.completedAt is null OR
(OP.completedAt is not null and OP.actionTaken = true and WF.completionDate is null));

Any suggestions to improve the execution time?

Try this index

CREATE INDEX ix1 ON  `DPE-WorkflowsAndMessages-INT` 
     (userId, completedAt ,  actionTaken, completionDate  )
WHERE  type = "AkvOpenItemDao"