[{_id:"5543333",title:"service 1",description:"des 1",status:"completed",amount:3000,user_id:"1",},{_id:"5543563",title:"service 2",description:"des 2",status:"in progress",amount:5000,user_id:"1",},{_id:"5542933",title:"service 3",description:"des 3",status:"completed",amount:4000,user_id:"1",},]

db.collection.aggregate([{"$match":{$expr:{"$eq":["$status","completed"]}}},{"$group":{"_id":"$user_id","total":{"$sum":"$amount"}}}])