You could be facing this problem for a variety of reasons:
 1. Your operator is not sending pop-ups
 2. You have not made a call or sms, and hence not received any pop-ups
 3. Operator has changed the USSD code response text, hence, we are unable to get balance from new format
 4. You may have task killers enabled which may have stopped mubble service and hence prevents mubble from finding the balance.
 5. You have installed some similar category apps which is dismissing pop-ups.
 
 If you receive a pop up after making a call , Please send the screenshots of pop up coming
 after call and screenshot of the mubble balance page to care@mubble.in to fix this issue.