I downloaded a free Zoho Docs for my iPhone 4 from AppStore. Then I signed up. iPhone said it was successful and prompted to login, showing my newly created id and stars instead of the password. Everything looked OK, so I tapped to login.

1. I got a message, that id and password do not match. Why?

2. I reentered id and password manually. The same result.

So I signed up the second time requesting the SAME ID (I expected to get a message like this: "This ID is unavailable")

3. But the iPhone accepted this ID the second time.

And everything repeated 

Please help