When changing a username, the respective name does not change in scoreboards containing it.
To fix this issue store the player UUID as the name (In the scoreboard) and display the corresponding users name instead.
Linked issues
Comments 2
Duplicate of MC-50247 which was resolved as “Works As Intended”.
Hello!
After doing a quick browse of the web, this does seem to be a common problem. Hopefully, Mojang will iron this out in future patches.
All the best,
Woo