To verify that you have created an at job, use the atq command. In the following example, the atq command confirms that the at jobs that belong to jdoe have been submitted to the queue.
$ atq Rank Execution Date Owner Job Queue Job Name 1st Sep 7, 2019 23:45 jdoe 897543600.a a stdin 2nd Sep 8, 2019 19:30 jdoe 897355800.a a stdin 3rd Sep 10, 2019 04:00 jdoe 897732000.a a stdin