how to get private key of old receiving address in blockchain.info. I have passphrase!
Unocioin


Did you mean Unocoin.com?

As far as I can tell, Unocoin operates custodial wallets (via BitGo and Blockchain.info APIs), meaning that only they have access to the private keys. If this is true and you've transferred bitcoin into your Unocoin wallet, then the only way to retrieve it is to log into your Unocoin.com account (or contact their technical support for assistance).

You could also try sending a message to bitcointalk user dashingriddler who apparently is a Unocoin employee.