I Like it...but confusing

I really like this app, and it keeps me on track drinking water. However, even after I bought the full version, after 21 days it said I needed to get the full version. So, I downloaded the full version again and transferred my data which disappeared. If I could figure out how to get the full version to work, I would give it 5 stars.

A Logical Person about Daily Water Pro, v3.6