[{_id:ObjectId("63e501cc2054071132171098"),name:"Ricky",discriminator:7706,registerTime:ISODate("2023-02-09T14:23:08.159Z"),friends:{"63e502f4e196ec7c04c4351e":{friendId:ObjectId("63e502f4e196ec7c04c4351e"),friendshipStatus:null,privateChannelId:ObjectId("63e66dd85eb6c3cc248ecc95"),active:true}}}]

db.collection.update({_id:ObjectId("63e501cc2054071132171098")},[{$set:{friends:{"$arrayToObject":{"$map":{"input":{"$objectToArray":"$friends"},"as":"f","in":{"$cond":{"if":{"$eq":["$$f.k","63e502f4e196ec7c04c4351e"]},"then":{"$mergeObjects":["$$f",{v:{"$mergeObjects":["$$f.v",{"friendshipStatus":1}]}}]},"else":"$$f"}}}}}}}])