[{"name":"A","startTime":1634626355,"endTime":1634631405},{"name":"A","startTime":1634631406,"endTime":1634631864},{"name":"A","startTime":1634631865,"endTime":1634656048},{"name":"A","startTime":1634712642,"endTime":1634718856},]

db.collection.aggregate([{$set:{startDateTime:{$toDate:{$multiply:["$startTime",1000]}},endDateTime:{$toDate:{$multiply:["$endTime",1000]}}},},{$sort:{startDateTime:1,endDateTime:1}},{$group:{_id:null,data:{$push:"$$ROOT"}}},{$set:{data:{$reduce:{input:"$data",initialValue:[],in:{$cond:{if:{$or:[{$eq:[{$size:"$$value"},0]},{$gt:[{$dateDiff:{endDate:"$$this.startDateTime",startDate:{$last:"$$value.endDateTime"},unit:"minute"}},5]}]},then:{$concatArrays:["$$value",["$$this"]]},else:{$map:{input:"$$value",as:"data",in:{$cond:{if:{$eq:["$$data._id",{$last:"$$value._id"}]},then:{$mergeObjects:["$$data",{endDateTime:"$$this.endDateTime",endTime:"$$this.endTime"}]},else:"$$data"}}}}}}}}}},{$unwind:"$data"},{$replaceRoot:{newRoot:"$data"}}])