ORA-18746
Replay disabled because it reconnected to instance with Transaction Guard (TG) disabled
Cause
AC is disabled for the current request because the last replay attempt has reconnected to a database instance with TG disabled.
Action
Ensure that all database instances reachable via the connect URL have the same or compatible AC and TG configurations. Be careful when downgrading from TAC to AC and make sure all connections are drained during rolling upgrades.