input axis horizontal not set up in main menu?

hello guys i'm new with unity.

i just download game tank from unity assets and its works well. but when i tried to make main menu in that project i got an error "input axis horizontal is not set up". i already search it in unity for solving this and they said check spelling in the get.axis and i don't using that code in my script. when i tried make new project with exact same scene main menu and script that i used in the tanks project it works well. so can you help me with this?

nb: - i used 1 script and 1 button just to test the main menu scene

• sorry if my english is bad :)

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