Hi gabrbrac-1130 ,
To call this endpoint https://graph.microsoft.com/v1.0/me/contacts in Graph Explorer, please sign in with your microsoft user account. Give the permission contacts.Read from the tab modify permissions. Refer https://learn.microsoft.com/en-us/graph/api/user-list-contacts?view=graph-rest-1.0&tabs=http
Hope this helps.
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