Bank blocked my account due to unverified KYC, how to resolve quickly?

I am based in Chennai and use my bank account for daily transactions. Yesterday, I was notified that my account is frozen because of unverified KYC details. This was sudden and without prior notice. I submitted my documents while opening the account a year ago. I am unable to access my funds and worried about paying my bills. I need to resolve this urgently as it’s causing financial strain. What steps can I take to get my account unfrozen quickly?