I have been away for a little while and come back today to see what looked like a new message, I clicked on it and it said having been away for a while, as a welcome back I have a chance to win an iPhone 11 pro in their new rewards scheme. I did not realise it was an advert at first.
my Norton security clicked in in time to prevent me from going further.
I do think that MyFitnessPal has some obligation to their users to NOT have malicious advertising on their pages that are designed to make their users think it is genuine (it even had what looked like reviews from here saying how great the new MyFitnessPal rewards scheme was).
Stay safe everyone