I am currently working in a public sector bank but have now been selected for state civil services. However, I could not apply for a No Objection Certificate (NOC) at the time of the interview since the call letter did not mention it. But during document verification, an NOC is required. I have given a three months' resignation notice to the bank, which will be completed in a few days. What should I do now? If I receive a relieving letter, will it be sufficient?