Surrender Bug
I was in a ranked game when the enemy team surrendered. For some reason the game did not end and continued. It was a successful surrender 4 - 0. Around the same time an AFK player joined the game again. Never seen an issue like this.
2 Comments
Do you remember exactly what the surrender notification looked like? Was it white or yellow? Was it said exactly at the same time and beneath something a player said?
It's possible that you were tricked. A player can type out two seemingly separate messages at once and put enough characters (including spaces) in the first half to push the second half to a new line. They'll make the second half look like a system message or whisper. If you're paying attention you can tell it isn't either of those because it is white (the color of player chat text) and it will appear exactly at the same time as their message above it (though new lines have no time stamp, they can create a fake one).
https://i.gyazo.com/ea4233c3922cd032731b1e6ed36a0ce1.png
Though it could also be a bug, but I find it less likely. If the trick was what happened, please use a Support Ticket to report the player. They are basically cheating because this can have a huge impact on player's actions when they think the game is over or if they got a message from Riot etc.