Updated jQuery Not Working On iPhone

Updated jQuery Not Working On iPhone

I have no experience with jQuery. I want to upgrade the jQuery request from 1.11.3 to 3.3.1 on my site.

I changed a depreciated event alias (.load) from

 $(window).load (function() {...}); 

to

$(window).on ( "load", function() {...}); 

and updated the link from 1.11.3 to 3.3.1.

This works on my desktop and iPad but not on my iPhone iOS 11.3.1.

Is there a way I can fix this?  Thanks!