Hi @supriya and thanks for your query. Can you kindly confirm that you are using the Tobii Pro SDK Unity bindings in conjunction with the HTC Vive Pro?
In that case, please kindly get in touch with The Tobii Pro support directly for an answer to your question @ http://www.tobiipro.com/contact/contact-support/ and the team there will reply to you shortly.
Thanks for your understanding and best wishes.