The daily bonus earning screen is not active when earning gems, switching screens, or performing other such operations.
If the daily bonus screen does not appear, wait a little while after launching the app without performing any operations.
Also, the processing load of the app and device can sometimes cause medals to be awarded before the daily bonus screen or medal (coin) earning animation is displayed. This can make it appear as if medals were not earned when they actually were.
Please check the daily bonus screen that appears the following day to see if continuous activation is still occurring.