Library doesn't load internal folders with File Access

[Cwpute]

This happened on a relative's phone.
When opening Auxio, the loading circle shows up in the top left but it's full, and crucially the library doesn't load anything. If i switch to the traditional loading system it works again.

This behavior was experienced alongside another two bugs:

1. the first one already reported in File not loading when opened from third party app #1153: Auxio cannot load audio from a folder it's not been authorized to with File Access system… except the folder was among the authorized folders !
2. the directory path of a USB key with music was added to the File Access system. While it cannot find music in internal directories it was pointed to, if i plug the USB key in, it can reach music files from that key, but still not from the internal storage !

Which makes me think somehow Auxio is prevented from reaching internal folders. But why ? i don't know.