A:AnswerHello Kitty! If you want to activate or deactivate the child lock function, press the Kitchen Timer button for 3 seconds.
The display will show ON when the oven is locked, and
then re-displays the time. You may also find this information on page 10 of the user manual. I have provided the link below.
(https://downloadcenter.samsung.com/content/UM/201911/20191122104255594/ME4000R_ME19R7041FS_AA_EN-MES-CFR.pdf)
Thanks for choosing Samsung. ^Nic