P400 chipless update problem - Update failed

[P400 chipless update problem - Update failed]

Step 4 from your instructions here https://www.2manuals.com/product_info.php?cPath=107&products_id=1851 suggest to check firmware after update:

Step 4
Now check current firmware version ( how to check ).
If firmware version is FA20I4 - firmware has been uploaded successfully. You can go to next Step.
If NO - restart printer and try once more time.

My initial firmware is FA20I4 and your chipless one is FA20I4 too. So I'm checking firmware after this "update failed" message and seeing the same FA20I4 20/04/2018, so I can't tell whether to proceed to the next step or not, according to your instruction. Is it normal in this case to continue with buying the Activation code and following to the next step?

Thanks.

[P400 chipless update problem - Update failed]

Have a SC-P400 with FA20I4 20/04/2018 firmware from Epson. Following this instruction https://www.2manuals.com/product_info.php?cPath=107&products_id=1851 . Printer does something, but each time I get "Update failed" message (please see picture). Tried several times with a solid USB cable on different USB ports - no success. Please advise something.