Visualization not showing up in iOS Safari, requires page refresh

Hi, I’m trying to do a bar chart, and it’s working spectacularly on desktop, but I’m having an issue on mobile devices. On first-time view of the page, the chart is not showing up on iOS Safari on my iPhone 4 and iPad 2. Then after a page refresh, it shows up. I don’t think it’s a caching issue because it always takes a page refresh to get the chart to show up regardless of whether it has been loaded before. Any thoughts? Thanks.