Attach method throws preg_replace(): Parameter mismatch - php

Question

I have been dealing with this ErrorException when trying to add data to a pivot table in Laravel.
When I use a dummy array data ie
$service->features()->attach([1,2]); it works but when I use values from an array variable ie. $service->features()->attach($featuresIds); wheareas $featuresIds has the value [1,2] it throws:
ErrorException (E_WARNING)
preg_replace(): Parameter mismatch, pattern is a string while replacement is an array.
My Service model class has:
<?php namespace App;
use Illuminate\Database\Eloquent\Model;
class Service extends Model {
protected $table = 'services';
public $timestamps = false;
protected $fillable = array('title', 'category', 'description', 'image', 'delivery_time', 'features', 'price', 'supplier', 'user_id');
protected $visible = array('id','title', 'category', 'description', 'image', 'delivery_time', 'features', 'price', 'supplier');
protected $dates = ['delivery_time'];
// public function features()
// {
// return $this->hasMany('Feature', 'id');
// }
public function supplier()
{
return $this->hasOne('Supplier', 'id');
}
public function category()
{
return $this->belongsTo('Category', 'id');
}
public function user()
{
return $this->belongsTo('App\User');
}
public function features()
{
return $this->belongsToMany('App\Feature')->withTimestamps();
}
}
My Feature model class has:
<?php namespace App;
use Illuminate\Database\Eloquent\Model;
class Feature extends Model {
protected $table = 'features';
// public $timestamps = true;
protected $fillable = array('description');
protected $visible = array('id','description');
public function services()
{
return $this->belongsTomany('App\Service');
}
}
My controller store method has:
public function store(ServiceRequest $request)
{
$service = Auth::user()->services()->create($request->all());
$featuresIds = $request->input('features');
$service->features()->attach($featuresIds);
return redirect('admin/service');
}
I have searched through many solutions online, but could not find a way to solve it. Help if you can detect what I am doing wrong.