Recipient address lookup failed

Aug 3, 2020
11
1
8
47
I'm using the

Proxmox Mail Gateway with Zimbra and when I enable Verify Receivers I get an error "Recipient address lookup failed" randomly in some existing accounts.
I suspect, but I'm not sure, that MTA Zimbra does not respond to verification in time.
I searched for address_verify_poll_delay in the Proxmox templates and didn't find it.
I don't know how to implement this parameter without breaking Proxmox.

Does anyone know how to do this?