Attempts to connect to Axway SFTP server result in publickey auth loopin

[Paul Ellis]

We are attempting to use openssh sftp to connect to a server that is 
running some version of the Axway SFTP server. After a publickey auth 
completes, the server resends publickey as a valid auth. This results in 
a loop as openssh sftp resubmits the publickey information. This seems 
similar to a discussion in 2014 that terminated with the thought that it 
might be nice if the client tracked this 
(https://lists.mindrot.org/pipermail/openssh-unix-dev/2014-August/032800.html). 
Is there any option we can use that will prevent this behavior? Attempts 
to contact Axway have failed as we’re not direct customers of theirs and 
the party actually running the server is blaming openssh.

debug1: Authentications that can continue: 
password,publickey,keyboard-interactive
debug3: start over, passed a different list 
password,publickey,keyboard-interactive
debug3: preferred publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /ssh/keys/secret.key
debug3: send_pubkey_test
debug3: send packet: type 50
debug2: we sent a publickey packet, wait for reply
debug3: receive packet: type 60
debug1: Server accepts key: pkalg ssh-rsa blen 535
debug2: input_userauth_pk_ok: fp 
SHA256:W0A/tu/vWh2vk0zHJUdTsZN9adQmS6x7fEbMbSTayfs
debug3: sign_and_send_pubkey: RSA 
SHA256:W0A/tu/vWh2vk0zHJUdTsZN9adQmS6x7fEbMbSTayfs
debug3: send packet: type 50
debug3: receive packet: type 51
Authenticated with partial success.
debug1: Authentications that can continue: 
password,publickey,keyboard-interactive
debug1: Offering RSA public key: /ssh/keys/secret.key
LOOP