I'm getting a notification that I've got a drive S.M.A.R.T. failure. e

I recently fitted a new replacement 3TB drive and I have not been able to access my my cloud mirror since. I am now getting the following warnings:The drive 1 self-check failed. File system check has detected errors on your configuration. Backup your data and recreate your drive configuration to resolve these errors. If problem remains, contact WD Support.
Have I lost all my data? If not how can I recover it?