If the software you are installing has been installed before, try uninstalling and reinstalling the current version.

If it still doesn't work,

Then either there is something wrong with the software package you are installing now,

Because the APK file has a signature mechanism, if the signature of the previous APK is inconsistent with the signature of the current APK, you will not be able to install your old version of the software in the cover installation. At this point, you need to uninstall before installing a new version of the software.