SOAP with Groovy script answers with 'ERROR' while PUT - groovy

Question

I have two same paths in my SOAP project, both of them use the same script
import groovy.json.JsonOutput
import groovy.json.JsonSlurper
class Response {
Integer code
String message
String accountId
}
// Match based on body
try {
def requestBody = mockRequest.getRequestContent()
def requestJson = new JsonSlurper().parseText(requestBody)
def phone = requestJson.phone as String
def email = requestJson.email as String
def accountId = requestJson.accountId as String
def response
if (phone == null || phone == "") {
response = new Response(code: 1011, message: 'Field phone is required')
} else if (phone == "[phone]") {
response = new Response(code: 1021, message: 'The phone field must be in the format [phone]')
} else if (email == "testt#testt.com") {
response = new Response(code: 1022, message: 'The email field must be in the format test#test.com')
} else {
response = new Response(code: 0, message: 'Success', accountId: accountId)
}
requestContext.response = JsonOutput.toJson(response).toString()
return "response"
} catch (Exception ex) {
requestContext.response = JsonOutput.toJson(new Response(code: 500, message: 'Emulator error: ' + ex.message)).toString()
return "response"
}
My problem is in sending a request to PUT method with the script. The request is
{
"phone":"[phone]",
"email":"test#notify1.com",
"accountId":"12345"
}
If I send POST, everything is okay
{
"message": "Success",
"code": 0,
"accountId": "12345"
}
If I send PUT, in a response I will see
{
"message": "Emulator error: Text must not be null or empty",
"code": 500,
"accountId": null
}
From the logs I see that the PUT script got requestContext as 'null'. What can be a problem?