The patch is a cat-and-mouse game. Game developers update their anti-cheat weekly. For a more permanent solution, consider these alternatives:

Always download from reputable community forums, as unofficial "fixed" versions may contain malware or unauthorized scripts.

In "fixed" releases like 3.3.6.4, the following issues are typically addressed:

Are you still experiencing any "App Not Installed" errors with this version?

To provide more tailored advice, are you planning to use this for a (e.g., Higgs Domino, PUBG) or a particular Android OS version ? X8 Speeder APK v3.3.6.8-gp Download for Android (Latest)

How to Install APK Files on your Android Phone (Best Method)