Database Transaction in Laravel controller

database_transaction.php

public function create(Request $request)
{
    $validator = Validator::make($request->all(), [
        'username' => 'required|unique:users|max:255',
        'email' => 'required|unique:users|max:255',
        'amount' => 'required',
    ]);

    if ($validator->fails()) {
        return redirect()->route('user.index')
        ->withErrors($validator)
        ->withInput();
    }

    DB::beginTransaction();

    try{
        // Step 1 : Create User
        $user = new User();
        $user->email = $request->email;
        $user->username = $request->username;
        $user->save();

        //Step 2 : Stripe Api Call

        //Step 3 : Amount Charged
        $user_amount = new UserSubscriptionAmount();
        $user_amount->user_id = $user->id;
        $user_amount->amount = $request->amount;
        $user_amount->save();

        DB::commit();

        return redirect()->route('user.index')->with('success','Thank You for your subscription');

    }catch(\Exception $e){
        DB::rollback();
        return redirect()->route('user.index')
        ->with('warning','Something Went Wrong!');
    }
}