App Store Updates: "We could not complete your purchase." "cancelled"

Is there an outage with the Mac App Store. I've seen this issue twice in the past two days, once on someone else's MacBook Pro, and now with mine. When you go to update an app, it says, "We could not complete your purchase." The only explanation given is "cancelled."

I have a MacBook Pro 15-inch (Mid-2012) running macOS Mojave 10.14.6

Hardware Overview:

  Model Name:	MacBook Pro
  Model Identifier:	MacBookPro9,1
  Processor Name:	Intel Core i7
  Processor Speed:	2.3 GHz
  Number of Processors:	1
  Total Number of Cores:	4
  L2 Cache (per Core):	256 KB
  L3 Cache:	6 MB
  Hyper-Threading Technology:	Enabled
  Memory:	16 GB
  Boot ROM Version:	231.0.0.0.0
  SMC Version (system):	2.1f175

System Software Overview:

  System Version:	macOS 10.14.6 (18G4032)
  Kernel Version:	Darwin 18.7.0
  Boot Volume:	Macintosh HD
  Boot Mode:	Normal
  Computer Name:	
  User Name:	
  Secure Virtual Memory:	Enabled
  System Integrity Protection:	Enabled
  Time since boot:	9 days 20:18