Firewalld allowing direct connections but not connections from load balancer after update

I've just recently upgraded a system from RHEL 8.5 to RHEL 8.10 which also upgraded firewalld from 0.9.3 to 0.9.11. In firewalld we have a postfix zone for port 25 connections and the only allowed devices in there are 2 direct connections and 2 connections from an F5 load balancer. The direct connections are working but connections from the load balancer aren't. I've had to turn firewalld off for now so that things still function but obviously want to resolve this so we can use it again. Error being received in load balancer is "unreachable - admin prohibited filter"