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Your code looks fine and it works for me (in v1076) via broadcasting to my Android devices.
However, if you are using the Player from the Android Player store, then it is the wrong version for v1076.
Because of some significant fixes, v1076 is not compatible with v108+.
Since you are a backer, you are entitled (I believe) to use the current v108 betas. If it appears in your TGC 'My Products' page, you might want to download and install that version of AGK. Just remember to uninstall v1076 first (saving any of your own work somewhere else so it doesn't get lost).
Cheers,
Ancient Lady
AGK Community Tester and AppGameKit Master