There are several reasons why your mobile payment might have failed.

• Insufficient funds: If your mobile payment has a spending limit, the purchase transaction will fail. Your account might also not have enough money to cover the cost of the transaction.
• Transaction has expired: Failure to respond to the confirmation message during the purchase process might cause your transaction to expire. Start a new transaction and respond to the confirmation message to make a purchase.  
• Payment disruption: Interference in your network may prevent confirmation messages from sending. In this case, the transaction might fail. Make sure that your network connection is stable before making a purchase.