I have Google Adsense several years ago and I have gotten purchased from Google several times too. One of my websites has been stopped showing ads (I manage to upgrade it and it is an welcome page only).
From long time I have not login to my Adsense account, but today I have login in and I found the total balance is -$86.53 USD as shown in the screen shot:
What's happening there? Do I have lost my balance? What I have to do?