[/** should return*/{"_id":ObjectId("63920f965d15e98e3d7c450c"),"first_name":"mymy","last_activity":1669278303.4341061,"username":null,"dates":{"29.11.2022":{},"30.11.2022":{}},"user_id":"1085116517"},/** should not return*/{"_id":ObjectId("63920f965d15e98e3d7c450d"),"first_name":"mymy","last_activity":1669278303.4341061,"username":null,"dates":{"30.11.2022":{}},"user_id":"1085116517"}]

db.collection.find({$expr:{$eq:[{},{"$getField":{"field":"29.11.2022","input":"$dates"}}]}})