I am not able to access the internal SD card of my Redmi 6 Pro mobile which runs MIUI version 184.108.40.206 and Android Version 9 PKQ1.180917.001. In settings it is showing storage 64 GB. However when I try to access the files, it is saying that /sdcard is not mounted. The "df -h" command in a terminal emulator shows that "/dev/block/dm-2" is mounted on "/data". But I am unable to access it. My applications are running smoothly except that it is unable to support any storage requirement and not able to retrieve the data already stored in the internal storage. Please note that my issue is with the internal memory and NOT the external memory card. In fact, I am also not able to access any external SD card, if provided.
Edit: As per the suggestion by @beeshyams, I installed "Storage Isolation" app from the given link and it gave the following warning. "Incompatible storage structure detected. The storage directory of current user is /sdcard instead of /storage/emulated/0........". It seems that if I mount the sdcard to the correct location, the problem may be solved. But how to do it?