Getting this error while creating a request using rest api.

[UDAYARANGA MUDIGERE]

Getting this error while creating a request using rest api.

Resulting Request: {"errorMessages":["Can not instantiate value of type [simple type, class com.atlassian.jira.rest.v2.issue.IssueUpdateBean] from JSON String; no single-String constructor/factory method"]}

Creating the request using CURL works fine but not in C#. Here is my json string. Can anyone share what might be the issue?

{
"fields": {
"summary": "This is a test email from custom maileater. Reject the request upon seeing it",
"issuetype": {
"name": "OPODS_GIS_MiscSupport"
},
"description": "This is a test email from custom maileater. Reject the request upon seeing it\r\n",
"project": {
"key": "PODSSUP"
}
}
}