Why Tamim Iqbal was given not out against Kyle Jamieson

There was a moment of controversy in the 15th over of the second ODI between New Zealand and Bangladesh when Tamim Iqbal survived an appeal for caught-and-bowled off fast bowler Kyle Jamieson.The incident happened when Iqbal was on 34, and he struck a full ball straight back. Jamieson, 6 feet 8 inches tall, then dived forward in his followthrough to take a low catch with both hands on the ball before momentum sent him to the floor. The on-field umpires asked Iqbal to wait as they asked the TV umpire Chris Gaffaney to adjudicate if the catch was clean with a soft-signal of out.