add note about expiry time of online meeting

Author: Yuyao Lian

api-reference/beta/resources/onlinemeeting.md

@@ -33,7 +33,8 @@ Inherits from [onlineMeetingBase](../resources/onlinemeetingbase.md).
 
 > [!NOTE]
 >
-> A bearer token is required for the `Authorization` header for all the methods listed in the previous table. For details about how to get the `token` for the `Authorization` header, see [Get access on behalf of a user](/graph/auth-v2-user?tabs=http#3-request-an-access-token).
+> - A bearer token is required for the `Authorization` header for all the methods listed in the previous table. For details about how to get the `token` for the `Authorization` header, see [Get access on behalf of a user](/graph/auth-v2-user?tabs=http#3-request-an-access-token).
+> - The expiry time for online meetings is set to 60 days after the meeting's start or end time. If the meeting is updated or activated before it expires, the expiry time will be extended by another 60 days.
 
 > [!CAUTION]
 >

api-reference/v1.0/resources/onlinemeeting.md

@@ -28,7 +28,8 @@ Contains information about a meeting, including the URL used to join a meeting,
 
 > [!NOTE]
 >
-> A bearer token is required for the `Authorization` header for all the methods listed in the previous table. For details about how to get the `token` for the `Authorization` header, see [Get access on behalf of a user](/graph/auth-v2-user?tabs=http#3-request-an-access-token).
+> - A bearer token is required for the `Authorization` header for all the methods listed in the previous table. For details about how to get the `token` for the `Authorization` header, see [Get access on behalf of a user](/graph/auth-v2-user?tabs=http#3-request-an-access-token).
+> - The expiry time for online meetings is set to 60 days after the meeting's start or end time. If the meeting is updated or activated before it expires, the expiry time will be extended by another 60 days.
 
 > [!CAUTION]
 > Teams live events was not removed on September 30, 2024, as previously announced. You can continue to use Teams live events; however, to get the latest new features and experiences, we recommend that you use [Teams town halls](https://support.microsoft.com/en-us/office/switch-from-microsoft-teams-live-events-to-town-halls-c71bf6e2-ece1-4809-900e-51271f39ac72) and the [Microsoft Graph virtual event townhall APIs](../resources/virtualeventtownhall.md) instead.