Hi Amit,
I tried the same. Added my Public IP to Administration->Configuration->Security Zones with webservice checked
But no luck. It is giving following response as before.
HTTP/1.1 403 Forbidden
Server: nginx
Date: Thu, 03 Jan 2019 11:27:36 GMT
Content-Type: text/plain; charset=utf-8
Content-Length: 25
Connection: keep-alive
Pragma: no-cache
Cache-Control: no-cache
Expires: Thu, 03 Jan 2019 11:27:36 GMT
X-UA-Compatible: IE=edge
X-XSS-Protection: 1; mode=block
Vary: Accept-Encoding
Content-Encoding: gzip
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