How to add Messenger icon using Socicon

Hello,

I’m using Zakra Free Theme with Socicon plugin to add social icons to my header top bar. I would like to add the Messenger icon there. I’ve added other icons (FB, Twitter, Instagram) without problems. But when I tried to add Messenger, it doesn’t show the Messenger icon. I have Social icons widget in the header top bar. There, I clicked on Add Icon, typed my Messenger link (that starts with httsp://m.me), but the icon doesn’t show up. My question is how can I add Messenger to my top bar using Socicon plugin?

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