Hi, @John Peter
According to the screenshot of your error, the operation cannot be executed because the target object is not found, so you need to check if the parameter object exists and is entered correctly.
You can use the following command to get the correct remote server URL.
Get-MigrationEndpoint | Format-List Identity, RemoteServer
The procedure can be found in the following article
Use PowerShell to move mailboxes | Microsoft Learn
New-MoveRequest (ExchangePowerShell) | Microsoft Learn
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