Chosen Solution
It says 0 bytes free of 256 TB after trying to create a folder inside PHONE (Beside SDCARD)… Is it permanently corrupted? I can access my phone without problems. I tried running virus scans already. Here is the photo
In looking at the photo of the folder, the name looks corrupted (not recognized by the system). Have you tried another name or just leave it “untitled folder” as a test? If it accepts the “untitled folder” as good, then try renaming it to a conventional name, without ANY special characters in it. Cheers!