Pool member not found error for a node that doesn't exist in the config

I am running LTM 11.4.1 HF7. I am getting this in the LTM log 4 to 6 times a minute:

Nov 25 09:22:02 F5-LTM-TMC-01 err mcpd[7840]: 01020036:3: The requested pool member (/WebTeam/pool_webextorg /Common/198.22.xx.xx http) was not found.

I have xx'd out part of the IP address for privacy.

The problem is that this 198.22.xx.xx address does not exist in the pool, or anywhere I can see in the configuration.

The pool mentioned in the error looks like this:

[root@F5-LTM-TMC-01:Active:Changes Pending] config  tmsh list ltm pool /WebTeam/pool_webextorg
ltm pool /WebTeam/pool_webextorg {
    load-balancing-mode least-connections-member
    members {
        /WebTeam/172.22.0.108:80 {
            address 172.22.0.108
            session monitor-enabled
            state up
        }
        /WebTeam/172.22.0.110:80 {
            address 172.22.0.110
            session monitor-enabled
            state up
        }
        /WebTeam/172.22.0.125:80 {
            address 172.22.0.125
            session monitor-enabled
            state up
        }
    }
    monitor /WebTeam/http_xxxxxxx
    partition WebTeam
}

If I search through all of the config for the offending address, nothing is found:

[root@F5-LTM-TMC-01:Active:Changes Pending] config  tmsh list | grep 198.22.xx.xx
[root@F5-LTM-TMC-01:Active:Changes Pending] config 

What could be triggering this frequent error for an IP address that doesn't even exist? Could something be continually querying the LTM for this pool member?