Indian fintech giant Paytm has received long-awaited approval from the country’s central bank to operate as a payment services provider for online merchants — just days after one of its Chinese investors sold its entire stake — marking a key regulatory breakthrough after months of setbacks and scrutiny. On Tuesday, the Reserve Bank of India (RBI) granted “in-principle” approval to Paytm’s Payment Services unit to operate as an online payment aggregator, parent company One97 Communications said i...