Veeam Backup very slow backup rate 21.1 GB read at 5 MB/s

We are using Veeam backup to backup from iscsi map drive to another iscsi map drive. We have gigabit connections. the speed is very very slow 02/12/2022 23:51:17 :: Sample (M:) (2.7 TB) 21.1 GB read at 5 MB/s