Shizuku problem solved | You need to take an extra step 

Many manufacturers have made modifications to the Android system that prevent Shizuku from working properly.

MIUI (Xiaomi, POCO)

Enable “USB debugging (Security options)” in “Developer options”. Note that this is a separate option from “USB debugging”.

ColorOS (OPPO & OnePlus)

Disable “Permission monitoring” in “Developer options”

Flyme (Meizu)

Disable “Flyme payment protection” in “Developer options”

Realme 

Turn on developer mode> go to developer settings> scroll down and find allow disable permission monitoring> allow it