I had this happen to me, so I presume I didn't see or recognize the popup. I was level 10 , I think I started last week . checking where is the bug report, but starting over is no trouble .
User error leading to Savegame Wipe : on an unlogged session, go to this page. the game start, from scratch. Log in to kongregate . Congratulations, you just wiped your own savegame !
I'm not sure if I get this comment correctly. Is this something that happened to you or what you assume what other players have done when they lost their progress? In general there is a popup after the Kong login that asks you, if you want to use the save from server or continue the local game and override the server version.
Please create a bug report when you lost your progress because of this and add some additional information about your level, starting date etc.
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Thanks, I've replied to your bug report!