I don't have my 12 word question but I do have my PIN and my computers MAC address
I'm pretty sure Hive is like the other web wallets in that they literally can't access your funds, they are encrypted. You would have been told in no uncertain terms to keep those 12 words safe and secure, it is not their fault if you haven't done that. Passwords are not recoverable on other web wallets either (e.g. blockchain.info).

Good luck, there's a chance some polite emails to their support may yield something if you have enough info for them to investigate but don't be surprised if they can't help.

Next time, store your funds somewhere safer and just keep day-to-day funds on the web wallet.