There are times when I go into the achievement list there are two of each achievement.
It will go away eventually, the extra achievements will go away but it's pretty annoying.
I have come across this bug several times
Linked issues
Attachments
Comments 2
Thank you for your report!
We're tracking this issue in MCPE-38111, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
Quick Links:
📓 Issue Guidelines – 💬 Community Support – 📧 Mojang Support – ✍️ Feedback and Suggestions – 📖 Game Wiki
I came across this once on my switch, and I saw something like 7500/7600 gamerscore even thou it's not possible.