Why did my bio get deleted when I cleared my cache/cookies?
Are you talking about on SO or on Meta? Your SO profile appears fine; your Meta one is empty, but I suspect you just never filled it out. If you were using an unregistered account accidentally (i.e. you forgot to log in), it would've persisted until you deleted your cookies. If that's the case and you know the user ID of the other account, you can get a moderator to merge it into your registered account