I checked our appstore logs and it seems OK.. Maybe there was some issue reaching the appstore? Our appstore is on DigitalOcean which didn't have downtime yesterday (afaict).
Back in the day, we had grand ideas to allow people to buy apps (like in smartphones) etc . This is why when you install an app it goes into the appstore with a "purchase" and uninstall results in an "unpurchase". In Cloudron 9, we have removed all this since it's all unused and just making empty calls to the appstore.