iMac Restore

I had a major problem with my iMac, took it to Apple Stores twice to restore it to no avail. THE PROBLEM started when I attached a WD Easy Store 8TB back up device. The computer, iPhone and iPad started acting erratic. I pulled the plug on the internet providers modem, tried restoring everything and my cpu. Than it was asking for 2nd authentication numbers on my computer, Everything was going crazy. I just checked my email for my iCloud acct and it saiD that The erase of Deb&rsqo;s started at 1:19 pm on 11/30/19 and open it with my password. I did encrypt the file. vault when I set it up and unencrypted before I tried to restore it. Is that what what the Deb&rsqo;s means?

Thanking you in advance,