I am creating events using microsoft graph (using .net sdk) and i found out that 2 events have same id with in a mailbox - graph

Question

Is this a valid scenario or a bug? Both the events are copied below.
{
"#odata.etag": "W/\"xyy/ioMMpU+5PhLPRGcb5AAAHWKktw==\"",
"id": "AAMkADZlNDUzMDYxLTQ2OTEtNDNiOC1hMDNhLTY1ZjAyMTYwZTBkOQBGAAAAAACPfBk217UgTYo6zKN7dzZsBwDHLL_KgwylT7k_Es9EZxvkAAAAAAENAADHLL_KgwylT7k_Es9EZxvkAAAdZ_YbAAA=",
"subject": "TestUtilityRunNow7_51",
"bodyPreview": "",
"body": {
"contentType": "html",
"content": "\r\n\r\n\r\n\r\n \r\n\r\n\r\n"
},
"start": {
"dateTime": "2019-03-08T12:57:15.0000000",
"timeZone": "UTC"
},
"end": {
"dateTime": "2019-03-08T13:02:15.0000000",
"timeZone": "UTC"
},
"location": {
"displayName": "",
"locationType": "default",
"uniqueIdType": "unknown",
"address": {},
"coordinates": {}
},
"attendees": [
{
"type": "resource",
"status": {
"response": "none",
"time": "0001-01-01T00:00:00Z"
},
"emailAddress": {
"name": "Training Room",
"address": "trainingroom#wmexchangeid.onmicrosoft.com"
}
}
],
"organizer": {
"emailAddress": {
"name": "Ravinder Singh Chahal",
"address": "ravindersingh.chahal#wmexchangeid.onmicrosoft.com"
}
}
}
{
"#odata.etag": "W/\"xyy/ioMMpU+5PhLPRGcb5AAAHWKiVA==\"",
"id": "AAMkADZlNDUzMDYxLTQ2OTEtNDNiOC1hMDNhLTY1ZjAyMTYwZTBkOQBGAAAAAACPfBk217UgTYo6zKN7dzZsBwDHLL_KgwylT7k_Es9EZxvkAAAAAAENAADHLL_KgwylT7k_Es9EZxvkAAAdZ_YBAAA=",
"subject": "TestUtilityRunNow7_25",
"bodyPreview": "",
"body": {
"contentType": "html",
"content": "\r\n\r\n\r\n\r\n \r\n\r\n\r\n"
},
"start": {
"dateTime": "2019-03-08T12:30:59.0000000",
"timeZone": "UTC"
},
"end": {
"dateTime": "2019-03-08T12:35:59.0000000",
"timeZone": "UTC"
},
"location": {
"displayName": "",
"locationType": "default",
"uniqueIdType": "unknown",
"address": {},
"coordinates": {}
},
"attendees": [
{
"type": "resource",
"status": {
"response": "none",
"time": "0001-01-01T00:00:00Z"
},
"emailAddress": {
"name": "Training Room",
"address": "trainingroom#wmexchangeid.onmicrosoft.com"
}
}
],
"organizer": {
"emailAddress": {
"name": "Ravinder Singh Chahal",
"address": "ravindersingh.chahal#wmexchangeid.onmicrosoft.com"
}
}
}