Dell uses a couple of manufacturer for TPM and Nuvoton is one of them.  Just like BIOS firmware, it won't update if firmware file doesn't match with the hardware (TPM). It seems that you stopped short at downloading the file before attempting to run update.  These are steps in the update process: Check status to see error is resolved.
I have already installed the latest BIOS Version/Date Dell Inc. 1.19.0, 14/9/2022 And have all relevant Dell and Microsoft Updates However, the TPM still shows the error message that it needs a firmware update   Please can someone in Dell assist? Kind regards, M [IMAGE]      
TPM Firmware Upgrade needed for XPS 15 7590