How to get ItemsForSale.user field using pipeline

Moralis General
#1

following is my lookup code to get the seller/user for the ItemsForSale, but it doesn’t project anything

 { lookup: { from: "ItemsForSale", 
      let: { "token_id" : "$token_id"},
      pipeline:[{ 
        $match: {
          isSold: { $ne : true  },
          $expr: { $and: [{
            $eq: [ "$tokenId", "$$token_id" ]
          }]}}
      },
      { "$addFields": { seller:"$user" } }],
      as: "prices" 
    }}