Restarting carousel event paused on iPad and iPhones - iphone

Question

I recently worked out a solution to another problem involving carousels on another post, but I found one issue when it comes to restarting the auto transitions from panel to the next on iPhones and iPads. (They won't restart.)
Here's a link to my original post and solution: Vanilla JS carousel next/prev button killing mouseover event pause
Here's a link to a JSFiddle containing my solution: https://jsfiddle.net/npzu90do/
After posting that solution I found that everything worked as it should accept the auto transition from one panel to the next stopped if you ever clicked the 'Prev' and 'Next' buttons on the sides. So I added this code to help restart the auto panel movement if you clicked outside the carousel.
document.getElementsByTagName("body").onclick = function(e) {
if(e.target != document.getElementById('carousel')) {
intervalID=setInterval(carouselPlus,speed,1)
}
}
Which works perfectly on all browsers except if you are on an iPad or iPhone.
I tried adding the following but that stopped the carousel from auto-starting due to errors in all browsers.
let touchEvent = 'ontouchstart' in window ? 'touchstart' : 'click';
document.getElementsByTagName("body").addEventListener(touchEvent, function(e) {
if(e.target != document.getElementById('carousel')) {
intervalID=setInterval(carouselPlus,speed,1)
}
});
Any suggestions?