Unable to access sharepoint and just disappear sites.

Last year I purchased Power BI pro license for single user. I have found few other apps including sharepoint. I started using sharepoint using the same credential. It was ok till today morning. But suddenly everything disappear. I don't understand why this is happened. How can I recover my site? If license is the issue , then I should get notified but not. What to do , I don't know. Any suggestion would be very helpful.