这个问题怎么解决？

vot

Translated to English:

If you see duplicated user group icons in the "Online legend",
then you need to update the forum cache settings:
1. Go to AdminCP - Global - Optimisation - Forum Cache Settings
2. Set the Forum Home Cache valid time to 900
3. Set the Thread Cache valid period to 900
4. Submit your changes
5. Clean all the cahe in AdminCP - Tools - Update cache:
    Data cache + Template cache + DIY custom styles cache