test_app/app/Models/UserCert.php

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class UserCert extends Model
{
    const UPDATED_AT = null;
    protected $table='user_cert';
    protected $fillable = ['user_id',
        'recom_id','agent_id','recom_audit',
        'recom_audit_desc','agent_audit','agent_audit_desc'];
    public function user()
    {
        return $this->belongsTo('App\Models\User','user_id','id');
    }
}