Hi krishnamurthy.durairaj ,
I assume that you're using route via http assertion to call the Expedia Supplier, you may add audit details assertion just after the route via http assertion, and show the content-type of the response using context variable ${response.http.allheadervalues}
The content-type header should look like,
Content-Type:text/plain;charset=UTF-8
You can check if the charset of the content-type is set properly.
If the charset is not correct, you may,
1. ask Expedia Supplier to return correct content-type
or
2. use Validate or Change Content Type assertion to change the content-type of response (put it after route via http assertion)
Regards,
Mark