JSON losing quotes when I use jsonconvert.deserializeobject

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C#

JSON

cURL

I am receiving from another website a curl request with json.
An example request would be

curl -X PUT -H "Content-Type: application/json" -d '{"c_id":"487672","amount":10}' http://xxxx/api/b2

This is just some test code to try and see the values...

[HttpPut]
public void Confirmation(HttpRequestMessage request)
{
    var content = request.Content;
    string jsonContent = content.ReadAsStringAsync().Result;
    CreateUpdate cpu = JsonConvert.DeserializeObject<CreateUpdate>(jsonContent);
    string acuid = cpu.c_id;
    return;
}

If I run using the above curl the value of the jsonContent string is

'{c_id:487672,amount:10}'

And as a result the code breaks and the acuid string is not populated.

What I have tried:

As a test I changed the curl to

curl -X PUT -H "Content-Type: application/json" -d "{'c_id':'487672','amount':10}' http://xxxx/api/b2

i.e. replacing the double quotes with single quotes.

{'c_id':'487672','amount':10}

This time my acuid variable is populated correctly.

My question is, what do I need to do to allow the original curl to be read without losing it's quotes.