add_alert_check issue

Cannot access offset of type string on string in /opt/observium/html/pages/add_alert_check.inc.php:46

#0: (unknown function) called at [/opt/observium/html/pages/add_alert_check.inc.php:46]

41:

42: ksort($config['entities']);

43:

44: foreach ($config['entities'] as $entity_type => $entity_type_array) {

45:

46: if (!$entity_type_array['hide']) {

47: //echo '<option value="' . generate_url(array('page' => 'group_add', 'entity_type' => $entity_type)) . '" ' . ($entity_type == $vars['entity_type'] ? ' selected' : '') . '>' . $entity_type . '</option>';

48:

49: echo '<btn class="btn" style="margin: 5px;"><a href="' . generate_url([ 'page' => 'add_alert_check', 'entity_type' => $entity_type ]) . '">' .

50: get_icon($config['entities'][$entity_type]['icon']) . ' ' . nicecase($entity_type) . '</a></btn>';

51:

#1: include called at [/opt/observium/html/index.php:258]

253: </div>

254: </div>

255: <div class="col-xl-8 col-lg-12">';

256: }

257:

258: include($page_file);

259: echo '</div>';

260: }

261:

262: // Register default panel if custom not set

263: if (!isset($GLOBALS['cache_html']['page_panel'])) {