Laravel add foreign key on migration file

i have this structure on card_price table in database:

CREATE TABLE IF NOT EXISTS `card_price` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `card_price` varchar(255) COLLATE utf8_unicode_ci NOT NULL,
  `user_id` tinyint(3) unsigned NOT NULL,
  `created_at` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
  `updated_at` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=1 ;

and this structure for users:

CREATE TABLE IF NOT EXISTS `users` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(20) COLLATE utf8_unicode_ci NOT NULL,
  `family` varchar(25) COLLATE utf8_unicode_ci NOT NULL,
  `username` varchar(15) COLLATE utf8_unicode_ci NOT NULL,
  `password` varchar(64) COLLATE utf8_unicode_ci NOT NULL,
  `email` varchar(20) COLLATE utf8_unicode_ci NOT NULL,
  `created_at` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
  `updated_at` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=1 ;

i'm creating this tables with migration files such as:

card_price:

Schema::create('card_price',function(Blueprint $table){
    $table->increments('id');
    $table->string('card_price');
    $table->tinyInteger('user_id')->unsigned();
    $table->foreign('user_id')->references('id')->on('users');
    $table->timestamps();
});

and users:

Schema::create('users', function (Blueprint $table) {
    $table->increments('id');
    $table->string('name','20');
    $table->string('family','25');
    $table->string('username','15');
    $table->string('password','64');
    $table->string('email','20');
    $table->string('remember_token','100');
    $table->timestamps();
});

with this migration files i'm trying to create foreign key with user_id on card_price table and id on users table. unfortunately i get this error:

  [Illuminate\Database\QueryException]
  SQLSTATE[HY000]: General error: 1215 Cannot add foreign key constraint (SQL
  : alter table `card_price` add constraint card_price_user_id_foreign foreig
  n key (`user_id`) references `users` (`id`))

  [PDOException]
  SQLSTATE[HY000]: General error: 1215 Cannot add foreign key constraint

via Chebli Mohamed