db={"user":[{"_id":ObjectId("61e52e26fd6b5909358c902a"),"firstName":"Mike","lastName":"Jones"},{"_id":ObjectId("61e52e26fd6b5909358c902b"),"firstName":"Lebron","lastName":"James"}],"tier":[{"_id":1,"tier":"free","lastDays":9999,"price":0},{"_id":2,"tier":"trial","lastDays":14,"price":0},{"_id":3,"tier":"vip","lastDays":365,"price":100}],"tierRecord":[{"_id":1,"user_id":ObjectId("61e52e26fd6b5909358c902a"),"tier_id":2,"activeDate":ISODate("2022-01-01T11:23:25.184Z")},{"_id":2,"user_id":ObjectId("61e52e26fd6b5909358c902a"),"tier_id":3,"activeDate":ISODate("2022-01-15T12:10:22.153Z")}]}

db.user.aggregate([{"$match":{"_id":ObjectId("61e52e26fd6b5909358c902a")}},{"$lookup":{"from":"tierRecord","localField":"_id","foreignField":"user_id","as":"docs"}},{"$unwind":"$docs"},{"$lookup":{"from":"tier","localField":"docs.tier_id","foreignField":"_id","as":"tiers"}},{"$project":{firstName:1,lastName:1,activeDate:"$docs.activeDate",lastDays:{$first:"$tiers.lastDays"},tier:{$first:"$tiers.tier"},endDate:{$dateAdd:{startDate:"$docs.activeDate",unit:"day",amount:{$first:"$tiers.lastDays"}}}}},{"$sort":{endDate:-1}},{"$limit":1}])