Server says I am out of space in volume but I am not

I get a message on the top left of the user interface telling me that I am out of space. It tells me that it will delete until i have enough storage space to continue. I checked my volume where the backups are being stored and i have over 1.5TB of storage space available. Can you tell me what could be causing this?

Thank you.

Hi Steve,

What file system is the backup volume? If it is BTRFS then you should read

Also, check the Global Soft File System quota is not set too low:

Kind regards,