why I can't see my name in yahoo answer?

Currently about 14% of all users have a ? for the nickname and about 80% have a shadow avatar. This is based on the first 100 listed on the leaderboard. Yahoo is obviously working on something and you will just have to wait for it to be fixed. There is nothing you can do.

Yahoo Answers seems to be having some technical difficulties today. It's happened a lot in the last few months. Their financial troubles probably led to greatly reduced staff overseeing this part of their business.

It is just a yahoo Glitch , has been going on for 2 days now .Hopefully it will get better soon .

The question mark is a glitch that will go away as soon as Yahoo fix it. You can do nothing about it. You can also not change your picture anymore. No if you are anonymous it is not displayed.

An ongoing bug - nothing we can do - have to wait for Yahoo to decide to fix it.

That is a longstanding glitch with the avatars. Ignore it.

Because i change it to a ?