GraphQL Unkown argument "price_gt" on field of type Query

With MongoDBAtlas I am trying to query products in my database which are greater than a certain price. Here is my query:

query findProducts{
  product(price_gt: 2000)
  {
            id,
            price
          }
    }

Here is the structure of the query:

product(query: ProductQueryInput): Product

Here is the relevant extract of my GraphQL schema:

input ProductQueryInput {
    price_gt: String
}

When I run the code I get the error:

{
  "data": null,
  "errors": [
    {
      "message": "Unknown argument \"price_gt\" on field \"product\" of type \"Query\".",
      "locations": [
        {
          "line": 33,
          "column": 11
        }
      ]
    }
  ]
}

I am a beginner with mongoDB so may be missing something obvious, but given the query is structured like it is and price_gt is in the schema as a input, I would have assumed it would just work.

Try this

product(query: {price_gt: 2000}) {
  id,
  price
}