I don't actually have the seed orelse I would have simply imported the address and signed a message from blockchain wallet itself.
The only things I have is: "Wallet-id & password" which gives me access to the blockchain wallet.
I hope the email verification works as it's my last hope perhaps.

This is enough, login to your blockchain wallet, go to Secuity Settings and then Backup Phrase.
Click on the Backup Funds and follow the instructions.
There you gonna get your 12 word seed which you can import in Electrum.
It's easy.
I even made a guide, see below
