Drive going offline

I have had this 3TB device for over 3 years. Occasional it acts up and goes offline, I reset it and it works again for a few weeks. Recently it has gotten worse.
I have been transferring video files to and from my iPad, also to and from my PC.
After a number of transfers, e.g. 5. The drive will go offline.
My Network Info
MyCloud has a fixed IP.
It is connected via a Gigabit Ethernet switch to the router.
Front light is Blue, rear lights are green, so visually all looks ok.
I can ping the device, no problem.
My home network has the following devices and these work all the time with no issues.
4 Fire TV’s
7 Amcrest security cameras
5 Sonos speakers
1 Sonos Bridge
2 Alexa devices
An Apple TV
2 Smart TV’s
Wireless printer
4 TP Link smart plugs
6 TP Link smart lights
Two wireless cable boxes
Two wired cable boxes
Three wireless access points
Three gigabit Ethernet switches
3iPads, 2 iPhones
Two PC’s running windows 10
Internet provider Fronitier 60MB
The MyCloud has 1.4 TB free, the data on the drive is as follows
Music
Pictures
Videos
I have tried both types of reset, but this has not helped.
I would appreciated some help here, before I throw the thing out the window:(

Transferring how? Using what app or software?

Have you tried turning off all other devices as a troubleshooting test?

What happens if you connect the My Cloud directly to the router rather than the network switch? Or is your router one of those that cause problems with the My Cloud per this link?

Hi and thanks for the speedy reply. My router is an AT&T Arris, that’s why I have the router connected via a switch.
Yes, in terms of other devices I have tried turning them off, no difference.
After resetting the drive today, it is available on my PC’s widows 10.
However it is offline to my apple devices, Two iPads and an iPhone.
I am transferring files from my camera roll in the iPad, one of the options is to save to MyCloud. As I said earlier, this does work for a few files then stops. However today I can’t access MyCloud from any of my apple devices.