Database
[{"centId":"261FB12F","servId":"CBBFEC62","year":"2020","month":"05"},{"centId":"261FB12F","servId":"CBBFEC62","year":"2020","month":"06"},{"centId":"261FB12F","servId":"CBBFEC62","year":"2020","month":"07"},{"centId":"261FB12F","servId":"CBBFEC62","year":"2020","month":"08"},{"centId":"261FB12F","servId":"CBBFEC62","year":"2020","month":"04"},{"centId":"261FB12F","servId":"CBBFEC62","year":"2021","month":"05"}]
Query
db.collection.aggregate({$match:{$expr:{$and:[{$eq:["$centId","261FB12F"]},{$eq:["$servId","CBBFEC62"]},{$ne:["$year","2020"]},{$ne:["$month","06"]}]}}})