Comment by umeshunni

RuPay isn't an implementation of UPI - it's an alternate payment network like STAR etc in the US. As a matter of fact, it's only recently that RuPay and UPI were connected:

From 8 June 2022, RBI allowed the linking of RuPay credit cards with India's Unified Payments Interface (UPI). In the absence of a physical card, customers can use their credit limit through for transactions.