That has been reported almost every day since release. Yesterday I spent many hours trying to to complete 3 wins for the daily, I won most games and not a single one counted because all players now are quitting before the winning player reaches 40 prestige. I talked to a few of those losers, some claim that they weren't aware of this massive bug, others never replied. So, I can assume that many players are now using this bug as a way to penalize the winner.

Zos is provoking a horrible behavior on this mini game that should be used for fun. It's impossible to understand why they keep it as it is. In ALL games when a player quits the remaining opponent gets the victory.

Also they should let a player quit with no time penalty and no rewards. It's another non sense to give a losing player a time penalty for resigning. It's insane to force a losing player to keep in game after giving up: https://forums.elderscrollsonline.com/en/discussion/610342/tales-of-tribute-needs-a-proper-option-to-resign-with-no-penalty

This is all reported since the release, and nothing is fixed.