the file size is bigger than the maximum allowed

[Skyfay]

Hey, I would like to share a file through my send server.
I get this message: error: the file size is 8.24 GiB, bigger than the maximum allowed of 2.50 GiB
But my send server allows 15 GiB. Is that a client limit?

Command i used: ffsend u -h https://example.com -p 1234 -d 2 -e 1d 'example.file'

System: Ubuntu 20.04 Server

Thanks for help.