Income tax return has been selected under risk management process

@ Saimahender Reddy Note the account number that you gave for refund and once you login to income tax website, goto Profile Settings -> Prevalidate Your Bank Account.If the account that you gave for refund is listed there and in the last column(Status) it says 'Validated' or 'Validated and EVC enabled' it means your account is prevalidated. If its not there or says 'Request Submitted' it means its not. In order to add the account (if its not there) follow the instructions here
Once you enter the bank details and submit for pre validation, you should receive an sms or email almost immediately if it was successful. Hope it helps

I finally got my refund for the revision of AY17-18 that I filed in October 2017. I had got the risk assessment mail, then the refund failed due to PAN not linked with DBS a/c given for refund(even though it was linked with my Aadhaar and PAN with DBS and not getting any help from DBS officials and the usual scriptted reply from ITD) . I filed the service request for refund reissue with an HDFC account which I prevalidated and enabled EVC. The long wait for years to get refund is finally over. I think the refund works only with the banks given in the ITD portal(in the Generate EVC Code section) though there is not confirmation from them on this aas well.

Before you proceed with refund reissue make sure you have a bank account which is 'Validated and EVC enabled' (Status) in the Profile Settings->prevalidate Your bank account. Make sure that EVC works by going to your netbanking and generating an EVC  in My Account->Generate EVC->Generate EVC through Netbanking(you should receive an SMS with the alphanumeric code).I chose a bank which is listed there(HDFC), I guess support for other banks are limited but please anyone confirm if they received refund in a bank not in this list.

For guys who received the PAN not linked,login to ITD website go to MyAccount->Service Request->New Request->Refund Reissue(Request Category) and click submit you should see the refund listed that has failed(if its not there wait another day). Click Submit next to it. Enter new bank details(that is already EVC enabled as explained before) and it will send you a new EVC code again to the mobile. Enter the new EVC code and place the request. You should get the refund in about 2 working days. This is how I finally got it after the long circus with ITD after these years. Good luck to the rest of the guys and thanks to everyone who helped and replied in the forum. 

@ Kush Dev, yes indeed, finally such a relief.  I see in the TRACES website like @ Saif and others mentioned that TDS details are incomplete so even if the new ITR forms are there, its practically useless. I'll take a break and wait for a couple of months till they are all in order. ITD has become a real pain these days.