HTTP POST Error Problem with Parameter json_data

Other Hardware Home Automation
4

I tried, this way

char PostData[] = "&json_data={"operation":"core/create","class":"UserRequest","output_fields":"id","comment":"loquesea","fields":{"org_id":"1","title": "prueba_hospital","description":"prueba"}}"

and

char PostData[] ="json_data={"operation":"core/create","class":"UserRequest","output_fields":"id","comment":"loquesea","fields":{"org_id":"1","title": "prueba_hospital","description":"prueba"}}"

but I still do not get positive results