Hi @Alla Brusova
I do not recommend that you use the access token in Graph Explorer in production, you should create your own application in Azure AD for easy management.
The default lifetime of an access token is 1 hour, and the lifetime of an access token can be extended up to 24 hours by creating a token lifetime policy. After 24 hours you will have to re-authenticate to obtain a new access token.
However, you can also roll over a new access token with a refresh token to avoid sending a new authentication request. Refresh tokens have a lifetime of up to 90 days.
Hope this helps.
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