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Perhaps the game app on your mobile was malicious, so you had such a problem.
Right now, I'm asking you to check the steps below. Check App Update > Log Out Game > Restart Device > Open Game & Log In.
Lives can also be lost through an update to the game, your own device or by restarting your device, which clears a certain amount of memory, depending on your device. We therefore recommend limiting the number of messages and lives that you save; a full mailbox can also affect the functionality of the game.
Don't forget that you can always request plenty more lives at any time from your friends! Also if you use a King account instead of Facebook, you will not encounter this issue.