If the above method doesn't work, It's highly possible that this is a problem on their side. Blockchain.info is a buggy wallet and you will see it from time to time particularly in these times where they are receiving high loads of traffic and it's holiday season so they might have reduced their staffs ??
My advice is to get in contact with their support and please make every reply in detailed like what methods have you already tried etc. If possible also include some proofs.
You can also follow up your problem in their social media's below:
Facebook: https://www.facebook.com/blockchain
Twitter: https://twitter.com/blockchain
On the other hand, if you want to access your funds asap. You can import it in electrum
*When electrum prompts you to enter your seed, Click options and tick the BIP39 Seed Box
*Please note that when importing, your funds will be accessible on both wallets which is why it's highly advisable to transfer them in a new wallet (with different seed/PK's) once the network has stabilized to avoid high fees