HELP!!! Variables are invalid JSON: Unexpected string in JSON at position 76.

[wai0901]

I received this message while using Shopify GraphiQL app, and I deleted and reinstalled the apps a few times, still not able to solve it, anyone can help me, thanks.

Error code showing : 

Variables are invalid JSON: Unexpected string in JSON at position 76.

GraphiQL code

mutation scriptTagCreate($input: ScriptTagInput!) {
scriptTagCreate(input: $input) {
scriptTag {
id
}
userErrors {
field
message
}
}
}

Query Variables

{
  "input": {
    "src":"https://2e1fb002a865.ngrok.io/test-script.js"
    "displayScope": "ALL"
  }
}

[wai0901 · Accepted solution]

ended up I just missing a comma after "src"!!. lol,