This is properly addressing the customer's need the first time they call,thereby eliminating the need for the customer to follow up with a second call:

I agree with experts answer. Thanks for the invitation. .

Thanks invite. ........ I agree answer  Omar Saad Ibrahem

Thanks invite. ......... I leaveanswer Experts 

Thnaks

I think , it is Quality of Service

3- Quality of Service..............................................

I apologize for the answer I leave the answer to the experts, specialists in this field that's not my area I wish you only invite specialists only