You need 200 points from votes and accepts (+2 and +15 from accepts and +x from bounties count) to gain the
Mortarboard badge. The +100 from associating a trusted account does not count.
See this post on Meta Stack Exchange, and also this post.
Moreover, the badges are only calculated every few hours, so even if you did get 200 points from voting, you may not see it for a few hours.
Mortarboard bronze; awarded once
Earn more than 200 reputation in a single day
Reputation points earned for associating accounts do not count for the badge
Each "day" lasts from midnight UTC to immediately before midnight, UTC; days are not counted in local time
Exceeding the cap is defined as earning ≥200 reputation in one day from a combination of upvotes and accepts