If you regularly file return then here is very important news for you . You will not be able to file your next return if you have not linked your PAN card with your AADHAR card .Here is also a good news to solve the issue. You don’t need to go to an expert and pay fees for the same. You have not even to register on website . The simplest way is to SMS to income tax department from your registered mobile no !Below is steps to do so .
SMS to 567678 or 56161 from your registered mobile number in following format.
UIDPAN 123456789123 GUJBU2002R