Curl API request value in body always null - json

Question

I have the following controller I am trying to use Curl to test it. The problem is that fiscalId is always null its not reading my post body from curl.
Controler:
[Route("api/token")]
public class TokenController : Controller
{
[HttpPost("changefiscal")]
[Authorize]
public async Task<ActionResult> ChangeFiscal([FromBody] long fiscalId)
{
//fiscalId is always 0
}
}
I have checked the documentation here which says to use the -d parameter and post it as a json object. Unfortunately thats not working
curl -d '{"key1":"value1", "key2":"value2"}' -H "Content-Type: application/json" -X POST http://localhost:3000/data
I have tried
curl -d "fiscalId=21875" -H "Content-Type: application/json" -H "Authorization: Bearer XXX" -X POST -i http://localhost:5000/api/token/changefiscal
and
curl -d "{"fiscalId":"21875"}" -H "Content-Type: application/json" -H "Authorization: Bearer XXX" -X POST -i http://localhost:5000/api/token/changefiscal
and
curl -d "{"fiscalId":"21875"}" -H "Content-Type: application/json" -H "Authorization: Bearer XXX" -X POST -i http://localhost:5000/api/token/changefiscal
and
curl -d "{\"fiscalId\":\"21875\"}" -H "Content-Type: application/json" -H "Authorization: Bearer XXX" -X POST -i http://localhost:5000/api/token/changefiscal
and everything else i can think of
I can see in the log that it appears to be sending it
Rebuilt URL to: POST/
timeout on name lookup is not supported
getaddrinfo(3) failed for POST:80
Couldn't resolve host 'POST'
Closing connection 0 curl: (6) Couldn't resolve host 'POST'
timeout on name lookup is not supported
Trying ::1...
TCP_NODELAY set
Trying 127.0.0.1...
TCP_NODELAY set
Connected to localhost (127.0.0.1) port 5000 (#1)
POST /api/token/changefiscal HTTP/1.1
Host: localhost:5000
User-Agent: curl/7.53.1
Accept: /
Content-Type: application/json
Authorization: Bearer eyJhbGciOiJSUzI1NiIsImtpZCI6IjI2OTAzNzc0NjYyNzc4RDM1MzE2QUUwQUU1MjIyQUU1REIzM0M0NUEiLCJ0eXAiOiJKV1QiLCJ4NXQiOiJKcEEzZEdZbmVOTlRGcTRLNVNJcTVkc3p4Rm8ifQ.eyJuYmYiOjE1MTA1NjcxNzMsImV4cCI6MTUxMDU3MDc3MywiaXNzIjoiaHR0cDovL2xvY2FsaG9zdDo1MDAwIiwiYXVkIjpbImh0dHA6Ly9sb2NhbGhvc3Q6NTAwMC9yZXNvdXJjZXMiLCJ0ZXN0YXBpIl0sImNsaWVudF9pZCI6IlNlcnZpY2VBY2NvdW50QWNjZXNzIiwic3ViIjoiMjEyNDg1ODIiLCJhdXRoX3RpbWUiOjE1MTA1NjcxNzMsImlkcCI6ImxvY2FsIiwibmFtZSI6ImxpbGF3IiwiZS1tYWlsIjoibGlsYXdAZWcuZGsiLCJzY29wZSI6WyJvcGVuaWQiLCJwcm9maWxlIiwidGVzdGFwaSJdLCJhbXIiOlsicGFzc3dvcmQiXX0.Q_oJ-xOIKdTtGoRqJbtNjwLV82cQQLhJUVl2Ey-4riZdp45rPIrmfOw9VdknUOLpm8RYZ0iLFC31gCpn1vKb4zLiTmBuTuzYsKxnAvf-UkCj1L8soH4W2lCvx560bZeS7B67tJ4nK9t36OiMLQY4m-_NRTSRBs5QtsXBd5VQGPsTpxf_MxVbQm6Hj6Ot3FGRIa08gmwD3iEr9vsCU6732InbGzU26wtm-WLWp_A_k66Z29G8ms_U8x6gg-aOlQG9_0v_DEjTXCkKNcgWoL0IvaCC0psiYkdIjQxaOwz-e_fcqXpKEFmuoSqmGd1l-eMl3HimOomdOHwqploWGxnJ4Q
Content-Length: 7
upload completely sent off: 7 out of 7 bytes
However when i check fiscalId its always 0 i even tried to change fiscalId to a string and its just null.

Answer 1

When you POST data as JSON object, like -d '{"fiscalId": 21875}', your action method should expect some simple class with corresponding properties. In your case:
public class Dto
{
public long fiscalId {get; set;}
}
and
public async Task<ActionResult> ChangeFiscal([FromBody] Dto data)

Answer 2

Finally after more then an hour of playing with this I got it even though the content-Type is json its just sent as a string "'21875'" even though all the documentation shows sending it as JSon. For some reason the API isnt able to read it as a JSon Object but expects it just to be sent as a string.
curl POST -v -d "'21875'" -H "Content-Type: application/json" -H "Authorization: Bearer XXX" http://localhost:5000/api/token/changefiscal