GraphQL json request fails

Retired Boards Appdev Graphql Basics And Troubleshooting
1

The following GraphQL request to https://mystore.myshopify.com/admin/api/2021-07/graphql.json with Content-Type = application/json return error 400 - Bad request

{“query”: “mutation productCreate($input: ProductInput!) { productCreate(input: $input)
product {
id }
shop {
id }{ userErrors { field message } }
}”,
“variables”: { “input”: {“productType”:“Robe coton jersey”,“descriptionHtml”:“Robe coton jersey extensible bla bla …”,“status”:“ACTIVE”,“tags”:“SDC”,“title”:“Robe coton jersey Noir”,“vendor”:“Uniformes HFM”} }
}

Anybody can help ?

Thanks