TACACS Auth Errors

Version: 11.5.2 HF1

TACACS for Admin auth

Error:

Sep  9 19:32:55 hostname err sshd[22220]: pam_tacplus: (pam_tacplus) converse returned 19
Sep  9 19:32:55 hostname err sshd[22220]: pam_tacplus: that is: Conversation error
Sep  9 19:32:55 hostname err sshd[22220]: pam_tacplus: unable to obtain password

Migrated the UCS from an old appliance to a new one. All that has changed is the management IP and the Self IP addresses. Everything else is the same. The F5 can ping the TACACS+ server. This error does not occur with every login, it almost appears to show up at random in /var/log/secure.

Any tips?