When you are playing Yu-Gi-Oh! Duel Links nothing is more frustrating than having your match abruptly end thanks to a server error. There a few possibilities for why this could be occurring, one of which is that you’ve lost internet connection and the game has booted you from its servers. Given this title is pretty much always online, you will want to have a strong connection if you plan on playing anywhere. To fix this, either close the application and move to a more stable location, or restart your router before reopening Yu-Gi-Oh! Duel Links again. You can also sometimes just keep tapping the “Retry” button as it could have briefly lost connection to the server, but will quickly reestablish after a couple of tries.
The other possible issue is that Yu-Gi-Oh! Duel Links servers are overburdened due to the high amount of people trying to log on to the game. If this happens, there isn’t much you can do to fix it other than wait and try back a little later as it isn’t a problem on your end of the game. Usually, this will be accompanied by either a maintenance note in the top left corner of your screen, or an error message explaining that they’re “staggering log-ins.” Just be patient and give the game another try after a few minutes and you shouldn’t see this server error again. Make sure to always play important matches on a strong connection in this game, the last thing you want is to lose all of your Gate Keys thanks to bad luck with your internet.