How to make your staff less robotic?

Hi all,
I would really appreciate your help on this.
After an extensive research that I have worked on, we could be reducing our CHT by a good margin if we to work on reducing “Rework” (instances when things get repeated by clients and CSRs). I have noticed one of the reason of “rework” is when CSRs are asking unnecessary questions that do not relate to the enquiry it self. CSRs become robotic at times and do not think through the stages of the call which increase “rework”.
How to make our staff less robotic and get them to think through the stages of the call?

Thanks