I’ve been facing issues downloading apps and updates on the Mac App Store on Mojave for a while now. I invariable “We could not complete your purchase. cancelled” message (see screenshot) that is randomly possible to get through after a few retries. I looked around online and it seems like it was a bug that affected a number of users on Mojave but that it has been fixed on the server side by Apple. However, I continue to be afflicted by it! 
I also noticed that the App Store randomly doesn’t show me updates for apps. I got to know that a few apps needed updates after going to their store page.
So far I have tried all. the. tips. on these pages (except for the drastic nuke+pave/upgrade to Catalina ones,) tried unleashing CleanMyMac, and looked into clashes between App Store and iTunes (both have the same account and I reauthorised the computer) but to no avail. Anyone else here running into this issue/know what to do?
