https://www.youtube.com/watch?v=w_6GzuJWFgI
Near the end, we see that (1) he drew against someone, and (2) they cheated. So he gets refunded the points from playing the cheater, but the message says "You lost to someone who violated lichess TOS" instead of "You drew to someone who violated lichess TOS." Probably because lichess assumes you can't draw a cheater haha.
The only bug is that the message itself is incorrect. The overall result in terms of points is correct.