https://wccftech.com/latest-unc0ver-jailbreak-for-ios-13-3-v4-0-3-update-fixes-app-store-issues/

The Unc0ver team has released another update for its tool that fixes some major issues and bugs which were not initially addressed. With the version updated to 4.0.3, the team pledges that all issues pertaining to App Store on devices with A12 and A13 Bionic chips running iOS 13 to iOS 13.3  have been fixed. If you installed the jailbreak on your iPhone 11 and iPhone 11 Pro series, you might have faced issues related to downloading and updating apps.

The issues were pretty evident in the Unc0ver jailbreak's initial release for devices running A12 and A13 Bionic chips. The team updated its app soon after, it did not do much. However, with the latest v4.0.3 update, the team says that the issues have been taken care of for good. Apart from this, the latest build also comes with a number of other fixes.