Newbie here! I'm getting the same achievements again and again. Why is that?

which achievements? It could be because it is an achievement that has multiple tiers.

Most often questing. Yeah, that might be it. The event text doesn't say it though, but I looked in My achievements now and seems like they've several tiers to them. Thank you!

Yeah, sometimes when the event shows up that you got an achievement, it doesn't display the proper text to indicate which tier you've received. But especially with questing and some games and stuff, there are usually multiple tiers so if you're doing a lot of it you'll probably be getting lots of achievements (at least in the beginning). :)