Laravel Many to Many relation Cannot add foreign key constraint

I'm creating a ManyToMany relationship with the Laravel framework v.5.7. So I created three migrations.

Modules Table

Schema::create('modules', function (Blueprint $table) {
    $table->increments('id');
    $table->string('name')->unique();
    $table->integer('price');
});

Plans Table

Schema::create('plans', function (Blueprint $table) {
    $table->increments('id');
    $table->string('stripe_id')->unique();
    $table->integer('price');
    $table->integer('max_users');
    $table->timestamps();
});

Relation Table

Schema::create('plan_modules', function (Blueprint $table) {
    $table->increments('id');
    $table->integer('plan_id')->unsigend()->onDelete('cascade');
    $table->integer('module_id')->unsigend()->onDelete('cascade');
    // Keys
    $table->foreign('plan_id')->references('id')->on('plans');
    $table->foreign('module_id')->references('id')->on('modules');
});

Whe I run the migration I get General error: 1215 Cannot add foreign key constraint.

Dose anyone has a idea what is wrong with the migrations. The default engine for mysql is set to InnoDB.

via Chebli Mohamed