hook - Hooking Android method with Frida but .implementation() not

I am learning Frida, and trying to hook a method checkFlag and trying to modify the boolean flag from true to false. Below is my demo app code In normal scenario, the Toast with Flag is True is

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java - frida returning wrong overload of android method - Reverse Engineering Stack Exchange

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Hooked method contents ignored · Issue #371 · frida/frida · GitHub

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