Icon font in Private Use Area (PUA) on iOS overwritten by emojis

A set of clients in Kuwait is reporting that one of our main mobile application's icons has been replaced with inappropriate emojis (such as Bootstrap Glyphicon Search turning into lips and others). This issue is reported exclusively by iPhone users, and we are struggling to find a solution. Our initial observations suggest that there might be an overlap between the icon mapping and iOS emoji mapping. Could this be the reason for the problem, and can you provide assistance?

Icon font in Private Use Area (PUA) on iOS overwritten by emojis
 
 
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