UPDATE (4/8/2019): Issue has been resolved on latest Android game update (version 1.0.34056). If this issue has affected you, please open a support inquiry.
We’ve confirmed an issue with Drops resetting to 0 after logging in with the latest version of Android beta (1.0.34055). If you have experienced this issue, please open a support inquiry.
We also advise to avoid using Zwift on Android until a fix has been implemented.
Thank you for your patience!