This cmdlet is available only in Office 365 Security & Compliance Center PowerShell. For more information, see Office 365 Security & Compliance Center PowerShell (https://docs.microsoft.com/powershell/exchange/office-365-scc/office-365-scc-powershell).
Use the Remove-ComplianceTag cmdlet to remove labels from the Security & Compliance Center.
Remove-ComplianceTag
[-Identity] <PolicyIdParameter>
[-Confirm]
[-ForceDeletion]
[-WhatIf]
[<CommonParameters>]
You need to be assigned permissions in the Office 365 Security & Compliance Center before you can use this cmdlet
IRemove-ComplianceTag -Identity "HR Confidential"