In gmail, Add to calendar button not working properly in ics file header

I sent invitation mail with attachment of .ics file. but when mail is sent to the user, User have a .ics file header with message body and a attachment link

In ics file heade, when user click on add calendar button to add event in the calendar. it does not add event in the calendar and just loading after some time shows the message 'Calendar could not load the data. Please try reloading later.'

Here is my .ics file

BEGIN:VCALENDAR
PRODID:-//Google Inc//Google Calendar 70.9054//EN   
VERSION:2.0
CALSCALE:GREGORIAN
METHOD:PUBLISH
BEGIN:VEVENT
DTSTART;VALUE=DATE:20190514
DTEND;VALUE=DATE:20190515
RRULE:FREQ=DAILY;COUNT=2
DESCRIPTION:
LOCATION:Vrandawan Dham Colony\, Ujjain\, Madhya Pradesh 456010\, 
India
SEQUENCE:0
STATUS:CONFIRMED
SUMMARY:AllDRepeatDaily_times
TRANSP:TRANSPARENT
END:VEVENT
END:VCALENDAR`

I removed UID from Ics file but it does not work for me

I am thankful, If anyone help me regarding this issue

Solution

Below code works for me

BEGIN:VCALENDAR PRODID:-//Google Inc//Google Calendar 70.9054//EN VERSION:2.0 CALSCALE:GREGORIAN METHOD:PUBLISH BEGIN:VEVENT DTSTART:20190514 DTEND:20190515 RRULE:FREQ=DAILY;COUNT=2 DESCRIPTION: LOCATION: India SEQUENCE:0 STATUS:CONFIRMED SUMMARY:AllDRepeatDaily_times TRANSP:TRANSPARENT END:VEVENT END:VCALENDAR