Re-add ESXi hosts after IP address change

I've been backing up VMs in a vSphere 6.7 cluster with vCenter and 3 hosts. I had to change the mgmt IPs for the 3 hosts last week, so VMX does not recognize them. In Datacenter, only my vCenter server shows up. I'm trying to add the hosts back and I have two issues.

When I try to add the hosts using the new IP for the display name (which is how I had them listed with the old IPs), I get a message "There is already a server with the same Display Name." I am allowed to continue, but it seems odd since these are new IP addresses.

the bigger problem is that on the test connection, I get  the error "ESXi SSH/SCP Error: There was a problem while connecting to [IP address]:22." I have SSH enabled on the hosts and I'm able to telnet into the hosts from the machine where VMX is installed.

I have the VMX agent installed on the hosts, and I've tried different options for the server add. Any ideas how I can add my hosts back?

Thanks.