"To change the locking/unlocking sequence by following the owners manual. The procedure for unlocking linked with the "POWER" switch "

I had trouble with this too. I found that the manual for unlocking was wrong and you had to do the opposite. That is unlocking linked to Power switch, you had to use the sequence for unlocking linked to park position. Turn on, leave in park, hold down unlock button for 5 secs, release...doors will lock unlock to show it took the change.

The directions for locking are correct in the manual it is just the unlocking procedure that is wrong.