Response to a HTTP POST request that cannot be processed

Response to a HTTP POST request that cannot be processed

Hello everybody:

I am making an app for Android that sends many HTTP POST requests to my Zoho Reports account and I would like to know if there is any special or diferent response to those HTTP POST requests that cannot be processed because there are not more API units available. I want my app to be aware of this for the user to be notified about this in order he is able to make proper decision.

Thanks in advance!