Gamers furious as Pokemon Go RESETS their progress through the game
Angry monster hunters say update has sent them back to beginning of smash hit smartphone game
Millions of people have spent way too long catching Pokemon over the past few weeks.
But now some of them are worried all those hours may have been wasted after an update to the game wiped out their progress.
The problem occurred when developer Niantic released a new version of the Pokemon Go software.
When some players installed it, they found that they had been booted back to Level 1 - the status of new players when they first open up the game.
On Twitter, one man wrote: "Lost my #PokemonGO account with update. Level 18. What a joke of a game. I'm done. Permanently deleted. Nothing is worth this grief."
The popular Pokemon Go app has been plagued with bugs, crashes and downed servers since it was released three weeks ago.
This is one reason why creators Niantic were eager to announce they were releasing a new upgraded version of the smartphone app that promises to fix various issues.
It was released over the weekend and offered a number of tweaks.
But, they didn't mention anything about taking features out of the upgrade, which was available as of today.
One useful feature, that has now been removed is the tracking tool, which was used to show you how far away from each Pokemon you were by showing you footprints.
Previously, as gamers got closer to Pokemons the footsteps would gradually reduce from three to one or vice versa.
But now, the 0.31.0 version has removed this feature leaving users confused about how to find the creatures and it's still unclear whether the display order of the Pokemons is actually realtime or accurate.
And in a strange bug, users were reporting that smartphones wouldn't come out of the battery saving mode - so they'd be forced to close the app or restart the game.
The removal of both these key features wasn't listed in the app's official upgrade information on either the Apple App Store or Google Play Store.
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