She is absent--她现在不上班。 你这样跟他说，他就以为，你同事不上班，你也不上班，你们公司都不上班啦。
你可以这样跟他说：She is not here right now或者she is out of the office right now 或者She is not at her desk at the moment.或者She isn't in her office at the moment. 然后接着可以礼貌的多说一句：What can I help you?这样他就不会误解你了。