Device Specs: MacBook Pro with Retina display, Early 2015 8 GB RAM, i5 processor
I just recently upgraded to macOS Mojave with a clean installation through the recovery mode and started downloading already purchased apps like pages, keynote, garage band and so on. All other apps got downloaded just fine except iMovie. The download progresses to 20 Mb and immediately resets to 10.5 MB and the cycle continues, and after a while the download self terminates with no message.
I tried clearing Appstore cache : How to fix / Reset App Store app on Mac OSX - El Capitan
And since, iMovie was so important for me, I even reinstalled the OS (clean again) and tried downloading iMovie but it was to no avail.
P.S: I do have enough space in my volume.
Edit: I reverted back to OSX Yosemite, through the recovery mode, downloaded the compatible version of iMovie there (10.1.1) (latest version isn't compatible with Yosemite) upgraded to Mojave and tried updating iMovie to 10.1.9, however, the problem still persists. Yet, I do have the old version of iMovie which works for me. I don't know if the problem is compatibility with my Mac or something else.