diff --git a/calendar/inc/class.calendar_uiforms.inc.php b/calendar/inc/class.calendar_uiforms.inc.php
index 6d3102eb3c..3803539eab 100644
--- a/calendar/inc/class.calendar_uiforms.inc.php
+++ b/calendar/inc/class.calendar_uiforms.inc.php
@@ -2859,7 +2859,7 @@ class calendar_uiforms extends calendar_ui
 				{
 					$e = $s + $duration;
 					$end_date = $e-$daybegin > DAY_s ? lang(date('l',$e)).' '.date($this->common_prefs['dateformat'],$e).' ' : '';
-					$times[$s] = date($time_format,$s).' - '.$end_date.date($time_format,$e);
+					$times[Api\DateTime::to($s, Api\DateTime::ET2)] = date($time_format, $s) . ' - ' . $end_date . date($time_format, $e);
 				}
 				$sel_options[$n.'start'] = $times;
 			}
diff --git a/calendar/js/app.ts b/calendar/js/app.ts
index 3cb6e9a638..dc2acad1d1 100644
--- a/calendar/js/app.ts
+++ b/calendar/js/app.ts
@@ -1708,7 +1708,7 @@ export class CalendarApp extends EgwApp
 			// Make the Id from selected button by checking the index
 			var selectedId = _widget.id.match(/^select\[([0-9])\]$/i)[1];
 
-			var sTime = <et2_date> this.et2.getWidgetById(selectedId+'start');
+			var sTime = <Et2Select><unknown>this.et2.getWidgetById(selectedId + 'start');
 
 			//check the parent window is still open before to try to access it
 			if (window.opener && sTime)