In interactions dashboard, you can filter out callbacks as below

Here based on values in 'Users' column should be able to give you a clue whether an agent was involved with any particular callback.
Moreover, by clicking individual interaction, you can work with Details and Time-line tabs as below to find out what exactly happened during this callback. e.g. disconnect reason may be helpful.

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Cheers,
Sajid Abbas Malek
Al-Futtaim Technologies - Dubai
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