connection-limit= Gateway Timeout? Why

All routes are connected by OSPF to one main router, and 1 firewall rule is added to limit user connections.
however, when i enable this firewall and after a few hours of user connectivity, they all get: “Gateway Timeout”.

On Main Router

/ip firewall filter

add action=reject chain=forward connection-limit=1000,0 connection-state=new disabled=yes protocol=tcp reject-with=tcp-reset src-address=10.0.0.0/8

what’s wrong i’m doing?