Unified Payments Interface (UPI) was established by National Payments Corporation of India (NPCI) and is regulated by the Reserve Bank of India (RBI), starting around 2016. UPI apps on mobile platforms facilitate the linking of multiple bank accounts to a single device and assists in performing all transactions within seconds. Sometimes these transactions fail due to multiple reasons. Here a mathematical model concerning the reasons for transaction failure and managing them are developed through a system of non-linear ordinary differential equations. Approximate analytical expressions for the rate of transaction failure due to insufficiency or exceedance, incorrect input data, bad internet connection and successful UPI transactions are derived using Adomian Decomposition Method and Variational Iteration Method which are compared to their numerical solution. This paper shows that a successful transaction depends on maintaining a proper account balance, following UPI transaction limits per day of the application you use, entering correct UPI PIN, receiver details and ensuring stable internet connection with sufficient speed.

DOI: https://doi.org/10.21863/ijbri/2024.12.2.002