Anyway I also never received email about monthly bonus when I was still bronze, but I never received it since I became Silver as well.
So, Shuffle team doesn't notify the user about the monthly bonus through email message. Now I'm wondering what kind of error has happened that they sent the monthly bonus message to an ineligible user. Anyway, the support has confirmed that I got the message from verified email of Shuffle team, and it was one kind of misunderstanding.
I'm starting to ask myself "do we need to activate something to receive their promotional email?" because most email I received from Shuffle are all about deposit/withdrawal notification and login verification only.
Don't worry, the monthly bonus message was the only promotional message which I have received from Shuffle. All other emails from Shuffle is about the deposit and login

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