HDFC Bank — Account blocked as Welcome letter not delivered

Hi HDFC team,

I think HDFC is getting in worst bank.

I am new account holder opened account 10 days back also I got my welcome kit delivered at my home but yesterday I received message as below:
Dear MR.. GANESH JAGDISH PRASAD KURMI, Welcome Letter for A/c XXXXXXXXXX6732 has returned undelivered. Due to this, account has been blocked. Please visit your Branch to help us assist you.

How it is possible that welcome kit is delivered but not welcome letter.

I think I should close the account from HDFC this is the worst experience I have got.

Expecting reply ASAP.

ALSO ASAP doesn't means that you should take more than 1 day

Regards,
Ganesh Kurmi