cssd-back/app/Cycle.php

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Cycle extends Model
{
    public $fillable = ['name', 'date', 'user_id', 'cycle_number', 'sterilizer_id', 'note', 'verified'];
    public function user()
    {
        return $this->belongsTo('App\User');
    }
    public function packs()
    {
        return $this->belongsToMany('App\Pack', 'cycle_pack');
    }

}