I had worlds before i became a beta tester and i decided to leave the beta testing and when i logged on to minecraft when i no longer became a beta tester, all my worlds were deleted and i have no files

Played minecraft as normal, became a beta tester, left because i wanted to try some of the new features for non beta testers and as I installed minecraft after leaving the beta tester thing, and logged onto the game, all my worlds were gone and no files appeared on my phone.