Unable to write to new partitions

[Ralf Mardorf]

On Sat, 17 Mar 2018 23:39:47 +0800, Bret Busby did not reply to Colin
Watson's question:
>I suspect what you wanted to do was to modify the permissions on the
>*mount points* instead.  What does "ls -ld /media/bret/Data05
>/media/bret/Data06" say?

Let alone potential "id -u" or "attributes" issues.

Btw. take a look at explanations of "lsattr" and "umask".

My recommendation is to be even careful with mount points permissions
and instead to change permissions of directories on those partitions.