Guild Wars 2

I have the same issue with the Glider Basics Mastery. Also with the message ""need 0 mastery points to master this ability".

Character name: My Dog Is A Plant

I have just bought HoT and have been exploring its new areas for a while. I have played only one part of the Story but now when I walk around a HoT exclusive map to get experience for the Gliding mastery, the game freezes after a few minutes in game. This does not occur when I walk around Central Tyria. Any thoughts? Or is this a common bug that needs to be fixed. Because like this, my purchase of the expansion has no use to me

Thank you in advance