I get pay every month from Adsense. Normally, the estimated earnings is updated everyday. However, I have 0 since this month whereas my account is still active. Everything should be in good condition. Can anyone tell me what's happen?
You should take a look at the 'page views' if this figure is 0 then you have a problem of the code not being executed. If the figure is increasing then you just haven't received any clicks for this month.
You should take a look at your rankings because obviously if your rankings have dropped then your click rate will too since your not getting the amount of visitors as your expecting. Review the page views of the last 7 days to that of last month and the previous before that.
Other than that you should forward your concerns and questions to the adsense team who will be able to answer all these types of questions.