I am also facing a weird problem. Although my account is not deleted but my answers are being deleted. All other answers to the question is remaining though. Why is this happening?
In a move to attain a quality backlink from the Yahoo answers as it is now a popular means to get a back link from it, people are gonna spam it and get their accounts banned due to the supply of malicious content..!!
Yes, I agree. Use proxies when signing up for a new account and try to not to over-promote you page. That is usually the reason why you get banned. And among other things, post quality answers so you can be chosen as the best. You can easily move up if that process.
There are some categories were people ask really stupid questions (very easy to answer) about there boyfriend or girlfriend not liking them etc. Try to answer a broad array of (easy / stupid) questions and also ask questions that seem intelligent to some extent. If your not seen as a participant in the community and more as a spammer troll they will kick you out.
You need to contribute to the Yahoo answer community. Then only your account will not be deleted. Moreover you will be getting some decent traffic also to your website through yahoo answer.