I can't test it right now (Server is down) but I'm pretty sure u need to close your first <label> tag and add an <AnchorFill /> to it
To display them they way you want you will have to look into anchors and offsets
you could either just offset them each a certain distance OR anchor the top of one to the bottom of the one above it
which is a bit trickier
As for the functions what do you plan to do with QuestMasterUpdate() and QuestMasterReset()?
Edit: also you need to give your <Label>s different names currently both of them will be named "QuestMaster"