this is a simple step to deleted your email and phone number from blockchain, so if any people have a your email and your password and you make a blockchain password same with email password, i think you will lose your all bitcoin balance in blockchain. So you must make a second password in blockhain (dont same with blockchain password login).
Step:
- go to your email and search "blockchain" klik email from [email protected]
- klik unsubscribe, and your email and phone number will deleted from your blockchain account. :D