Try the following steps:
1.- To bypass this, open System Preferences and click Security & Privacy.
2.- In the “General” Tab click next to “mac.xpl” was blocked from use because it is not from am identifier developer. Click “Allow Anyway”. (See picture)
3.- Next time you open the aircraft you will received a message “macOS cannot verify the developer of “Mac.xpl”. Are you sure you want to open it?. Click on Open. (See picture)
It should not ask again for permission.