Paytm shares experience a significant decline of up to 9.88% after global broking firm Macquarie downgraded the company. Macquarie expressed concerns about Paytm's risk of customer exodus and reduces its target price. Paytm has faced regulatory issues, including a ban on Paytm Payments Bank. RBI Governor asserts little room for reviewing actions against Paytm. Market experts caution retail investors against purchasing Paytm shares until regulatory issues are resolved.