If you pause the download and exit the sim, then remove that particular .fspatch/fspackage file from your install location, then restart the sim and it should try again on that file.
The file will be located in the location chosen on the main install screen of MSFS. The default locations are shown below, but this may vary if you’ve chosen a custom install path:
Windows Store install:
%LOCALAPPDATA%\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalCache\Packages
Steam install:
%APPDATA%\Microsoft Flight Simulator\Packages
Boxed version install:
%LOCALAPPDATA%\MSFSPackages
Go to that folder and find the /Official/[OneStore or Steam] folder. In there, if you can find the file ending in .fspatch or .fspackage that is causing you issues, delete it, and restart the sim. It should then resume the install and redownload those problem files.
That should fix the problem, though you may have to repeat the process a few times with different files it gets stuck on