ical (ics file) not working on Mac calendar

I have a .ics file that works with outlook gmail and any calendar I tried. Mac calendar does not display errors but as a matter of fact it doesn't save the event. Obviously the file header type is text/calendar. Need help to get what is missing here. BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Technology//NONSGML Calendar//EN CALSCALE:GREGORIAN METHOD:PUBLISH BEGIN:VEVENT UID:20190218T094757-1209729636 CLASS:PUBLIC X-MICROSOFT-CDO-INTENDEDSTATUS:BUSY ORGANIZER;CN=robert:MAILTO:abc@[login to view URL] DTSTAMP:20190218T094757Z DTSTART;TZID=America/Panama:20190227T070000 DTEND;TZID=America/Panama:20190227T093000 LOCATION:berlin SUMMARY:test TRANSP:TRANSPARENT END:VEVENT END:VCALENDAR