How do you change your license plate to your steam name?

I have the setting to set all license plates to my steam username on Beamng but they're still either a normal, default license plate or supr_pig
^
(links to another thread I posted https://www.beamng.com/threads/all-number-plates-on-every-car-save-to-supr-pig.79351/#post-1324879 )

I just want it to be my steam name

 

Sure, the code is:

103403