Paid usernames expire 2 years after purchase. Free ones do not expire. You can go to “edit” “more” and from there should be able to click on the “renew” button.
Your are trying to use the stacks wallets with your seed for your identity. If you want to put your identity using the same seed as for the stacks holdings then you have to
create a new seed for stacks wallet
transfer your identity to an address derived from your new seed.
I understand you found the blockstack browser using your 12 words seed already. Note, that there is a newer version: https://app.blockstack.org (with limited functionality)
Try yr seed phrase for yr hardware wallet. That worked for me. FOr some reason, hardware wallet itself failed (some BS about browser support), but seed worked.