MultiWAN policy gateway slow upload speed

[Bullz3y3]

In my client's site I deployed pfsense with 3 WANs and grouped into one and set LAN connection to go through that gateway. Internet access and download speeds are perfectly fine. However users started to complain saying cannot use filezilla to upload using (sftp). Port and everything is opened. Then few users couldn't submit forms with 100kbs of attachments in a https:// website. but sftp sometimes worked but most of the times did not work. Hence overall upload speed is drastically slow.

Please someone shed some light  :'(

[Shreeyashattal]

Firewall>lan>new rule>destination port (sftp)>default gateway> select any 1 gateway

loadbalance grouping will not work on ftp