Asynchronous get is behaving in strange manner

hey i am using asynchronous get but it behave strangely as at some time it gives output at some specific record and next time its not giving any output. can you help me.

The record will be null in RecordListener callback if the record is not found. Also, if no timeouts are set, it’s possible that RecordListener (onSuccess() or onFailure()) is never called.