(PvZ GW2) Automatic/manual save not working...

Basically, whenever I exit and re-enter the game, my save reverts to a previous state. This makes me lose hours of gameplay and progress... I've already had to replay the Zombies campaign about 4 times in total, in addition to leveling up more than 6 heroes to level 5, only for them to revert to level 1 immediately afterwards. Recently I was collecting gnomes around the map when the server crashed (it wasn't due to lack of internet), and when I returned, all the gnomes had disappeared from my collection... I'm seriously thinking about abandoning PvZ GW2, the game simply refuses to save my progress for no reason, and it's driving me crazy.