Cant add SingleValueExtendedProperties to Message

I'm trying to add a new SingleValueExtendedProperties to a message:

var requestBody = new Message
{
    SingleValueExtendedProperties = new List<SingleValueLegacyExtendedProperty>
    {
        new SingleValueLegacyExtendedProperty
        {
            Id = "String {66f5a359-4659-4830-9070-00047ec6ac6e} Name Color",
            Value = "Green",
        },
    },
};

var result = await _graphClient.Users[messageInfos.MailBoxId]
    .Messages[messageInfos.MessageId]
    .PatchAsync(requestBody);

In the result after the patch, the property is still null:

This is not a permission problem, because the permission is set to Mail.ReadWrite. Change the subject or move message is working.

Expected behavior

The SingleValueExtendedProperties is not null after the PatchAsync request.

How to reproduce

var requestBody = new Message
{
    SingleValueExtendedProperties = new List<SingleValueLegacyExtendedProperty>
    {
        new SingleValueLegacyExtendedProperty
        {
            Id = "String {66f5a359-4659-4830-9070-00047ec6ac6e} Name Color",
            Value = "Green",
        },
    },
};

var result = await _graphClient.Users[messageInfos.MailBoxId]
    .Messages[messageInfos.MessageId]
    .PatchAsync(requestBody);

SDK Version

5.77.0

Latest version known to work for scenario above?

No response

Known Workarounds

No response

Debug output

Click to expand log

```

</details>


### Configuration

_No response_

### Other information

_No response_

[MartinM85]

Extended properties are relationships, so they won't be returned in result of patch request.

https://learn.microsoft.com/en-us/graph/api/resources/message?view=graph-rest-1.0#relationships

Even if you want to get extended properties you need to specify the property in the filter

https://learn.microsoft.com/en-us/graph/api/singlevaluelegacyextendedproperty-get?view=graph-rest-1.0&tabs=http#get-a-resource-instance-expanded-with-an-extended-property-that-matches-a-filter

Ok. Thanks.