Nokia 8 does not read contents of SD Card after phone reset

Trying to solve the "settings has stopped " issue, I did a full reset, and then another issue came up. On re-inserting the external SD Card, the *Files* app (or any file manager) can see the contents, but gallery and music players don't see the media. And on connecting to the PC, the SD card shows only one or two folders, and nothing else. The SD card is a SanDisk microSDXC Class 10 64GB, which was initially formatted from within the Nokia 8 on first use, as was required for some reason.