Union dan pagination laravel

var $model_class = 'App\Modules\Calls\Models\Calls';
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$second     = $this->model_class::select(DB::raw('sys_rel.rel_to_module as module_name, sys_rel.rel_to_id as module_id, (SELECT CONCAT(contacts.contacts_first_name, " ", contacts.contacts_last_name) FROM contacts WHERE contacts.contacts_serial_id = module_id) AS calls_parent_id'))
                                                                ->join('sys_rel', 'sys_rel.rel_serial_id', '=', 'calls.rel_serial_id')
                                                                ->where('sys_rel.rel_to_module', '=', 'contacts')
                                                                ->where('calls.rel_serial_id', '>', 0);

$third      = $this->model_class::select(DB::raw('sys_rel.rel_to_module as module_name, sys_rel.rel_to_id as module_id, (SELECT org_name FROM org WHERE org.org_serial_id = module_id) AS calls_parent_id'))
                                                                ->join('sys_rel', 'sys_rel.rel_serial_id', '=', 'calls.rel_serial_id')
                                                                ->where('sys_rel.rel_to_module', '=', 'org')
                                                                ->where('calls.rel_serial_id', '>', 0);

$data       = this->model_class::select(DB::raw('sys_rel.rel_to_module as module_name, sys_rel.rel_to_id as module_id, (SELECT CONCAT(leads.leads_first_name, " ", leads.leads_last_name) FROM leads WHERE leads.leads_serial_id = module_id) AS calls_parent_id'))
                                                                ->join('sys_rel', 'sys_rel.rel_serial_id', '=', 'calls.rel_serial_id')
                                                                ->where('sys_rel.rel_to_module', '=', 'leads')
                                                                ->where('calls.rel_serial_id', '>', 0)
                                                                ->union($second)
                                                                ->union($third)
                                                                // ->Paginate(10)
                                                                ->get()->toArray();