Wrong response with update multiple.

Wrong response with update multiple.

Today I'm getting the wrong response fro the Update and insert Multiple records in ZOHO.
My API call which was working a few days ago today is getting a strange response which is not eaven a XML response but an simple web page :
<!DOCTYPE HTML>
<html>
<head>
<title>CRM Software, Customer Relationship Management - Zoho CRM</title>....

I'm using a API call formed like...  authtoken={api key}&scope=crmapi&version=4&xmlData={xml data}

Was there a change in the multiple API call ?  In the API documentation is not recorded !