You can ignore this.
There is already a new CA certificate i.e. appliance_ca.pem auto-generated and in place. This CA appliance_ca_1.pem is probably from an old discovery version which has been replaced by appliance_ca.pem.
You can check this from discovery command like, go to /usr/tideway/etc/ca/, check the present CA certificates. You will find 2 CA certificates i.e. appliance_ca.pem(current in use) and appliance_ca_1.pem(old one)