UnhandledPromiseRejectionWarning: MongoError: Unsupported projection option: sort is an error that is thrown when you pass sort options into mongoose schema methods.

I passed the sort and limit options inside the mongoose find method as a parameter which turned out to be wrong.

ProductSchema.statics = {
    filter (query, options){
       return this.find(query, options);
    }
}

Mongoose provides chainable methods with find that can be used for sort and limit.

let latestProduct = await productModel.filter({}).sort({ "date": -1 }).limit(1);

Unsupported projection option: sort — This error implies sort and limit are not valid options that you can pass inside mongoose find method.