Per Ramhound suggestion, I had to run one command line to save the new change :
(gwmi -class Lenovo_SaveBiosSettings -namespace root\wmi).SaveBiosSettings()
or (If your BIOS is password protected):
(gwmi -class Lenovo_SaveBiosSettings -namespace root\wmi).SaveBiosSettings("Password,Encoding,KbdLang;")
Thank you