I got a random event just now for an extra wizard quest. The thing is, I already got a bonus quest buff today, and when I went to the wizard quest, it said 16/16 quests done, so I cannot do the second extra quest.

I believe the bug originates something like this:

1. Finished all wizard quests: 15/15
2. Get an extra quest buff: 15/16
3. Do the extra quest: 16/16
4. Extra quest buff runs out: 16/15
5. Get a second extra quest buff: 16/16 (but I cannot do the extra quest)

Pretty sure this is not a bug and that's how it's supposed to work (:

In that case they should make it so you can only get the bonus quest buff once a day... Rather than having a second random event confusingly do nothing.

Not a huge deal or something the staff should prioritize by any means, though :)