Files are not copying

I’m using Macs in my studio my and My Cloud drive is connected to my router. I love it.

I have an issue though. I use the drive to back up my music session drives. When I drag anything (folders, files, etc.), it’s a crapshoot on whether or not the files will all get copied.

I have an existing folder (“FOLDER A”) with files in them. I drag a new “FOLDER A” and select to replace all contents and sometimes it’ll copy everything, sometimes it won’t … and sometimes it’ll just stop copying altogether.

Also…

I’m hard-wired into my router and file copying takes forever. 10-20 minutes for 300mb.

I’m wondering why the files and folders won’t copy over especially when replacing files? At the end of the day, I’ll just manually drag my day’s work onto the drive for backup and I’m seeing that almost all of the folders are missing files and data.

Any fix for this?