Removing characters in property transfer

Hi all,

Reposting this question, as I am still looking to get this back to work....

It has been several years since I last performed a load test with SOAP UI. In the test case, I am transferring the response from one call to another using the property transfer step. As the response from the api consists quotation marks which should not be transferred, I had the following script in the Xpath window of the property transfer step in order to remove those:

def response = messageExchange.responseContent
response = response.replace("""","")
messageExchange.modelItem.testStep.testCase.setPropertyValue("jsonResponse",response)

This used to work fine, but it no longer does. I now get an error; Content is not allowed in prolog. Any idea how I can get this back to work?

Txs!