You can stop the plain texts by texting the word STOP to 247262.
You can also disable it in your Account settings, or just make it clearer about what's going on. Go into the settings, select Notifications, then look at the first two sections, "Push Notification Settings" and "Text Message Settings". Adjust away! 🙂
I leave mine set to receive notifications via both methods. The duplicates don't bother me, and it tends to ensure that I get at least one of them in a timely manner, since sometimes one of them can lag the other by more than just a few minutes.
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