Error activating TPM - SMBIOSWriteFailed. OptiPlex 3020. BIOS: A20

PS C:\WINDOWS\TEMP> set-item DellSmbios:\TPMSecurity\TpmActivation Enabled -Password $Password
set-item : FAILURE.
At line:1 char:1
+ set-item DellSmbios:\TPMSecurity\TpmActivation Enabled -Password $Pas ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : WriteError: (DellSmbios:\TPMSecurity\TpmActivati
on:String) [Set-Item], InvalidOperationException
+ FullyQualifiedErrorId : SMBIOSWriteFailed,Microsoft.PowerShell.Commands.
SetItemCommand