According to the problem you described, it is preliminarily judged that the TV is in the mall display mode. When Samsung TV is in the mall mode, the TV will have a function prompt, and the set parameters cannot be saved.

Exit through the item menu as follows:

Press the program source key of the TV remote control to select the TV mode. Then press the item key, select Settings-Plug and Play-Enter a custom password or an initial password of 0000- Chinese-Home, and then exit the menu or follow the prompts to complete the settings.

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