After setting up unionfs merged folder of disks into poolOnly Writes to 1 Disk

I have sorted out the problems with seeing the merged folder of disks but now have found that it is only writing to one Disk - thats now full and wont write to anything else. I must have not done it right but followed Techno Dad video when I did it. See below my Filesystem

I’ve read another thread and it maybe the File name and path when setup so video folder was setup on one disk and will put that on that one disk instead of the least filled disk. I didn’t really understand it probably but it advised to remove data to free up 10-15% to make it green then move it back and should be fine.

This was a clean install of OMV so has it remembered the file layout from before on the disks?

Please can someone tell me in very lay terms what I need to do to fix this problem

Thanks

So how do I change this to be able to pool all my disks as one and be able to add more data because at the moment I can’t do anything as I keep getting the disk is full message

I want all 4 different disks that are of different sizes - I dont know where I need to find this that your asking for? I attached a screenshot above this isnt whats needed

I've just tried this and still got Full disk message when Ive tried to add

Which I did but when I added the data says disk is full. I changed it in the drop down of the Media folder as you can see above & saved it but this changed nothing when I added the data

Sorry I didnt scroll down - Ive now applied the settings and waiting for server to restart before I try again

Trying to reboot server throws a "An error has occurred" message and wont reboot the server

Rebooted & now working

Thank you for your help