HOW TO FIX CYDIA IMPACTOR STUCK ON PREFLIGHTINGAPPLICATION
METHOD 1 – REBOOT YOUR DEVICE
Firstly, restart your iPhone, iPad, or iPod touch and then proceed with the sideload process. While this is not a proper fix, rebooting usually solves most of the errors.
METHOD 2 – DELETE APP ID
Open Impactor and go to the Xcode tab. Now select the Delete App ID option.
If it still doesn’t work, try removing the app from your iOS device (in case it’s already installed). Once you have done that, try sideloading it again.
METHOD 3 – DOWNLOAD THE CORRECT IPA
If you think you have the incorrect IPA file, try another source. Sometimes you might end up downloading the older or obsolete versions of IPA files. This is bound to cause issues with newer devices and firmware versions.