"PromptPay Alert'' is a technology for sending and receiving notifications to pay. Biller can use their PromptPay ID to send notification to recipient. Once receives by recipient, a transaction can be made using their PromptPay ID as well. For example, shopping cart application can send notification using their PromptPay ID to the customer's registered PromptPay ID and device with preferred bank application. Payment can then be made by customer right away, or save for later before message becomes expired for postpay payment.