Unable to use theme copied to folder:

1. Phone system compatibility. The theme is not universal under different versions of ColorOS. Casual copying may cause the mobile phone crash.
2. The designer design theme spend a lot of labor. If they are copied and used casually, the designers are unwilling to design themes anymore.

Solution method:

1. If the phone built-in version of Theme Store is V4.5, this problem will not be solved. It can use themes that downloaded in Theme Store only.
2. The mobile phone built-in version (factory version) of Theme Store is under V4.5, you can  update after uninstalling the Theme Store version and back to the old version.
This operation is not recommended because the new version solves many bugs.
It's better to tell the user reason, because ColorOS 2.1 is now built in V4.5 and higher. It is unable to solve the issue of copy usage.
(The lowest version of realme is ColorOS5.0)