Put the summary of the bug you're having here
What I expected to happen was...:
Describe what you thought should happen here
What actually happened was...:
Describe what happened here
Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. Ich kann zu meinen Legancy Accout vor der Migration keine Daten ändern (z.B. E-Mail)
3. ...
Unfortunately, bugs need to be reported in English.
In additon, please use the WEB project (https://bugs.mojang.com/browse/WEB) to report bugs with web services, or contact Minecraft Support (https://help.minecraft.net/hc/en-us/requests/new) for help with account issues.