This incident happened in the 17th over of Delhi's innings, when Varun Chakravarthy was bowling. Hetmyer slogged one on the fourth ball of this over but Shubman Gill, standing at long-on, took a brilliant catch. KKR camp was celebrating the wicket and Hetmyer also reached the dugout, walking towards the pavilion.
When Hetmyer had crossed the boundary line, the umpire stopped him. After this Varun Chakravarthy's no ball was seen and this drama lasted for about 2 minutes. Hetmyer survived and he came out back on the field with joy. Varun's no-caused utter disappointment and it was visible on the entire team's face.