Android Question Reminder EventConstants

[ddefrain]

Hi Everyone
If I create a calendar event the reminder is ok for Me; I have one hour (60 Minutes) reminder in my calendar, but not for the attendants.
Some of them have 10 minutes, others 30 minutes
How can I configure the reminder to everyone for an hour?
Thank's in advance
Regards

addreminder(eventID)

    Sub addreminder(eventID As Int)
    Dim val As ContentValues
    val.Initialize
    val.PutString(rcon.EVENT_ID, eventID)
    val.PutInteger(rcon.METHOD, rcon.METHOD_ALERT)
    val.PutString(rcon.MINUTES, "60")
    Dim reminderuri As Uri =cr.Insert(rcon.CONTENT_URI,val)
    If reminderuri<> Null And reminderuri.IsInitialized Then
        Dim reminderID As Int = reminderuri.ParseId
        Log($"reminderID: ${reminderID}"$)
    End If
End Sub