[Users] Cloned account on moving server, incoming mail still goes to old inbox

[Adrian]

I've moved my mailserver to a new server with identical config but a
new server/MX name. Old and new mailservers are both running but the old
one is not receiving mails any more.

I set up a "new" and an "old" account on a Claws Mail app by
editing accountrc, copying the [Account: 1] values to a new [Account: 2]
section. I changed the server name in Account2 and made it the default.

Later I swapped the labels - renamed Account2 to Account1 and vice
versa, and swapped their order in the file.

It all works EXCEPT THAT incoming mails to the new server are arriving
in the Inbox of the OLD server's account.

Both accounts in accountrc have these values
inbox=#mh/Mailbox/inbox
local_inbox=#mh/Mailbox/inbox

How can I make incoming mails arrive in the new, live default account's
Inbox folder?

Thanks for any help on this.

Adrian