谷歌日历更新时区问题

Question

i am trying to update my existing event of google calender.

While update event i also want to update timezone too.

So while updating time zone i am getting this error.

string(517) "{
 "error": {
  "errors": [
   {
    "domain": "global",
    "reason": "invalidParameter",
    "message": "Value '[e-mail]' in content does not agree with value 'primary'. This can happen when a value set through a parameter is inconsistent with a value set in the request."
   }
  ],
  "code": 400,
  "message": "Value '[e-mail]' in content does not agree with value 'primary'. This can happen when a value set through a parameter is inconsistent with a value set in the request."
 }
}"

This code I am using for update timezone.

$event_id = 'event id';
$service = new Google_Service_Calendar($client);
$event = $service->events->get('primary', $event_id);

/* Updating timezone (**This is causing issue**) */             
$calendar = $service->calendars->get('primary');
$calendar->setTimeZone('Europe/Amsterdam');
$updatedCalendar = $service->calendars->update('primary', $calendar);

$event->setSummary($clientName); // Summery of calender 

$event->setDescription($treatmentname); // Description of calender

/* Update start time */
$startTime = '2018-11-01T08:00:00';  
$start = new Google_Service_Calendar_EventDateTime();
$start->setDateTime($startTime);
$event->setStart($start);

/* Update end time */
$endTime = '2018-11-01T09:00:00';
$end = new Google_Service_Calendar_EventDateTime();
$end->setDateTime($endTime);
$event->setEnd($end);

/* set single event not recurring */
$event->setSingleEvent(true);

$updatedEvent = $service->events->update('primary', $event->getId(), $event);