How to call rest API to start process in JAVA --- giving 400

I have simple payload as :
{
“caseID”:“12”,
“exceptionAmount”:“23”,
“type”:“Market”
}

I want to start the process with the above payload using RestTemplate.
But I am always getting 400 Bad requests.
It is working if I update my JSON as :

{
“caseID”:{“value”:“12”},
“exceptionAmount”:{“value”:“23”},
“type”:{“value”:“Market”}
}

Which REST endpoint do u mean?

@Artem_Smirnov
http://localhost:8080/engine-rest/process-definition/key/testProcess/start

@rahulnanda24 the correct format required for the REST API is as you noted. For more examples see REST API request body examples for starting a process instance