Mojave Backup Server Authentication Fail

It's sad that Apple is so busy designing dongles and thinking about new iPhones that making basic Mac software work as it should is not on the table, this is on the back-burner for sure.

The Problem: When I define a folder to be shared as a Time Machine volume via the Sharing control panel (this is a server functionality made possible in Mojave, however it does not seem to work). When I try to use the backup destination, I'm told that there is a problem with the network username or password. When I initially setup the TM volume and enter the credentials there is no issue reported. When I try to mount the volume in the Finder it immediately uses credentials from the keychain, I'm not prompted. When I try to disconnect the volume it reconnects immediately. Each time this fails you seemingly have to delete the TM destination on the client side and re-select, re-authenticate, re-define the encryption password.... WHAT A MESS! Any thoughts about this mess of an OS? Do you remember when things just worked and everything from Apple was not simply a PITA?

Error: Time Machine couldn’t complete the backup to “backup-server.local”.

"The network backup disk could not be accessed because there was a problem with the network username or password. You may need to re-select the backup disk and enter the correct username and password."

Thanks,

R