Huge rating drop after JAN15 update

In the recently concluded JAN15 long contest, I had solved 5 problems fully and 2 other problems partially.
Naturally I expected a rating increase, but today I noticed that even though correct submissions are shown on the contest page with a green tick on corresponding problems, my name is omitted from the ranklist and my rating has fallen sharply in excess of 4000 rating points.

Account page

Can anyone tell me the reason of this huge drop?

seems like a case of plagiarism.

Read Here for more details.

This might have happened due to plagiarism cases, your rating might have decreased due to possible case of cheating or plagiarism.

You can send an e-mail stating your concern to help@codechef.com . Check the blog about " how to get my ratings back ".

Read this link if you want to know more about plagiarism and how it is handled by codechef.

Contact number to get in touch with Codechef => Office: (022) - 30797709 (Weekdays 1:00 pm to 3:00 pm)