Have 126 bars, failed a level and tried to buy extra moves with the bars I have because I wanted to keep the Winning Streak goodies and the game tells me it cannot contact the store. Lost everything...very frustrating...
Could not tell you if that happens frequently...was the first time for me and I have have not attempted to buy anything during the game again. I play on the PC and I do know that there were no connection issues .
If you have a Windows 10 PC you can also download the app directly to your computer and play via the app instead of Facebook. You can download the game from here.