MyFitnessPal sent out an email titled: SUCCESS❗ You Just Earned This $40 Reward
Seems to expire 7/19/18
It's for $40 off $100. Check your email. YMMV as usual.
This one might be unique, I haven't received one in a while, so I'm not sure if they're always like this, but mine says, "You logged an impressive number of times this month, earning the Under Armour Dedication Reward."