Can we reset or forgot second password of the blockchain account ?
If you have an HD wallet you can restore your wallet using the backup phrase. If it's a non-HD wallet then the backup phrase isn't sufficient. How do you tell if it's an HD wallet or not? If the wallet was created during or after February 2016 then it's likely an HD wallet. Otherwise it has non-deterministic private keys and you need access to the decrypted wallet file that blockchain.info stores on their servers which you can only get if you know the second password.