Cannot update apple-touch-icon on iOS Safari

Hello,

I cannot seem to update the apple-touch-icon displayed for a website I'm developing on the home screen of Safari on my iPhone.

• I have tried Settings > Safari > Clear History and Website Data
• I have tried adding a url parameter (i.e. href="/apple-touch-icon.png?v=2")
• I have tried uploading a new apple-touch-icon.png on the server

The correct icon is displayed on my friend's iPhone but nothing I do seems to display it on my device.

My iPhone (iOS 11):

My friend's iPhone (iOS 10):

Any help on troubleshooting this issue would be highly appreciated.

Best,

Jimmy