How to free up space to install apps?

After installing a 32 GB SD card, having trouble installing apps. Because the OS is 5.x and not upgradable then adoptable storage isn't an option. How can I install apps when the system reports insufficient free space? Every app I've downloaded has been moved to SD card, yet, the prompt is to uninstall these apps. To reiterate, every app which I'm being prompted to uninstall has already been moved to external storage. Seems a conundrum. --------------------------- After resetting to factory default I then installed Disk Analysis for defrag on the system storage.