Connectivity to Memrise and two weeks progress lost
I have an iPad. Two weeks ago the app stopped showing me any leader board rankings. Finally today I logged in on the web (on the same iPad that I use Memrise) and noticed that my online profile showed none of my progress for he past two weeks or so.
Finally, I logged out and back into the app and the app resynchronized with the website losing all of my progress. 
Any ideas how to make sure this does not happen again? I am a pro member and take this learning quite seriously.
iOS 9.3.2
Firmware 6.02.00
Courses A1 and A2 Spanish
Memrise 2.1.20