I am not good in mail drafting but i want try of it.
Dear Sir / Ma'am,
This is bringing to your kind notice that Mr.XXXXXXXXX, selected for designation of XXXXXX in our Organization but he has not responded the acceptance of our offer letter. we are trying to get back him over the phone and mails but he could not responded the same.
Please advise the same.
8th June 2014 From India, Hyderabad
Check if this format would be of any help to you.
Dear Mr. XYZ,
This is in regard to your offer letter for the position of.................. dated...........
We would like to inform you that inspite of trying to reach you many times through mail/telephone, you did not respond.
We would take this oppurtunity to inform you that the company has come to a decision that you are not interested in the offer. The company would go ahead with other candidate selection.
We wish you all the best for a bright future and looking forward to work with you in the future.
ABC- Hr executive
8th June 2014 From India, Secunderabad