Error message with longer inputs

Using an API call, when I input a shorter prompt, I don’t get the following error. I do get the error when I input a longer prompt. I’ve increased the tokens so the figure is far above my input length. Know what the solution is? Here’s the error:

The service Name-of-my-API-call just returned an error (HTTP 400). Please consult their documentation to ensure your call is setup properly. Raw error:

{
"error": {
"message": "We could not parse the JSON body of your request. (HINT: This likely means you aren't using your HTTP library correctly. The OpenAI API expects a JSON payload, but what was sent was not valid JSON. If you have trouble figuring out how to fix this, please send an email to support@openai.com and include any relevant code you'd like help with.)",
"type": "invalid_request_error",
"param": null,
"code": null
}
}

Is it over 2,000 tokens in total?

Weird it would show a JSON error message for the larger one, though…

Good luck.