Hello Aspirant,

Don't worry even if you have lost your RBI office attendant admit card and your Registration number, because you can retrieve your Registration number from your E-mail Id or SMS, when you had registered for the exam you must have received your registration number on your e-mail ID as well as on SMS, so you have to search for little and once you get your Registration number then you can login to your application and can again download the Admit card. As the result is about to declare within few days so it is recommended that you should retrieve your Login credentials as soon as possible.

I hope this information helps you.

Good Luck!!