How to solve the error of statically calling non-static method 'update'?

Question

This is my function. I am getting an error in it, please help me to resolve this error and tell me why this error is appearing.

public function update(Request $request)
{
    $id = $request->id;
    $grade = Grade::find($id);

    $grade = $request->validate([
        'title' => 'required|string',
        'slig' => 'string',
        'description' => 'string',
    ]);

    $grade = Grade::update($grade);

    return [
        'staus' => 'success',
        'grade' => $grade,
    ];
}

Answer 1

First create an instance. But I don't think that's the real issue.

$newGrade = (new Grade())->update($grade);

return [
    'status' => 'success',
    'grade'  => $newGrade,
];

Try changing your method as follows:

$grade = Grade::findOrFail($request->id);

$validatedData = $request->validate([
    'title' => 'required|string',
    'slig' => 'string',
    'description' => 'string',
]);

$grade->update($validatedData);

return [
    'status' => 'success',
    'grade' => $grade,
];