I have the stickers in my album but I'm unable to get the achievement. When viewing the sticker album, nothing happens. Help :'( Solution: I looked at the required stickers on the achievement page and refreshed, it gave out the achievement then.

Give the site 10 minutes to catch up? Sometimes the cache takes a little bit to recognize that you have the stickers in your album, then try looking at the required achievement again instead of your sticker album.

it works now :) Thanks!