Why Harshal was allowed to bowl despite two waist-high no balls

Harshal Patel was allowed to continue despite bowling two waist-high no balls during the Sunrisers Hyderabad–Lucknow Super Giants IPL match. Under IPL rules, a delivery is deemed dangerous only if the umpire judges that it risks injuring the batter. While Harshal's first waist-high no-ball was relatively closer to the striker's body, the second one was well outside his bodyline.