Laravel 9 error route | The GET method is not supported - api

Question

I am having a problem fetching a list of certain customers (authenticated users) via API. When I use this route in Postman I receive the following error.
Symfony\Component\HttpKernel\Exception\MethodNotAllowedHttpException:
The GET method is not supported for this route. Supported methods:
POST. in file
D:\api\vendor\laravel\framework\src\Illuminate\Routing\AbstractRouteCollection.php
on line 118
api.php
Route::post('/register', [UserAuthController::class, 'register']);
Route::post('/login', [UserAuthController::class, 'login'])
->name('login');
Route::apiResource('/customer', CustomerController::class)
->middleware('auth:api');
Controller
class CustomerController extends Controller
{
public function index()
{
$customers = Customer::all();
return response([ 'customers' =>
CustomerResource::collection($customers),
'message' => 'Successful'], 200);
}
public function store(Request $request)
{
$data = $request->all();
$validator = Validator::make($data, [
'first_name'=>'required|max:120',
'email'=>'required|email|unique:users',
'password'=>'required|min:6'
]);
if($validator->fails()){
return response(['error' => $validator->errors(),
'Validation Error']);
}
$customer = Customer::create($data);
return response([ 'customer' => new CustomerResource($customer),
'message' => 'Success'], 200);
}
public function show(Customer $customer)
{
return response([ 'customer' => new CustomerResource($customer),
'message' => 'Success'], 200);
}
public function update(Request $request, Customer $customer)
{
$customer->update($request->all());
return response([ 'employee' => new CustomerResource($customer),
'message' => 'Success'], 200);
}
public function destroy(Customer $customer)
{
$customer->delete();
return response(['message' => 'Customer deleted']);
}
}

Answer 1

I solved this problem by adding Accept|json/application in headers of Postman.