What is Proximus M-Pay? October 12, 2016 05:07 Updated M-Pay is a free service offered on Proximus network by Belgacom in Belgium that allows users to pay digital purchases with their mobile phone. Visit Proximus support website for more information. Related articles How do I know if I have a M-Pay account? How do I configure my M-Pay account? What is the Boku Customer Care Portal? I got a message that said: "Sorry, your payment failed. No charges were made." What do I need to do to complete a payment?