Browse to /mnt/YTAPxxx-RRR/500000/2021-Jul-13/, there are those updated *.csv files. However, if you attempt to delete (rm) any one of this csv file, the error - rm: cannot remove `lpp_0902.csv': Text file busy.
Ever checked with these commands - lsof | grep -i 2021-Jul-13 or fuser /mnt/YTAPxxx-RRR/500000/2021-Jul-13/, both show none.
What's went wrong with these csv files? how to solve it?
lsof might not show anything open there, but that is a remote cifs share and could be open somewhere else that has DCS mounted (or mapped in windows)
suggest looking at the server that hosts that share and see what it shows for open files