Cisco Customer Support Engineer interview questions

Very typical questions, such as what are your strengths and weaknesses, describe a time where you have struggled and how you got through it. However, one interviewer was particularly insistent on asking what I would do if I encountered a problem I cannot solve--as in, I literally didn't have the knowledge or tools to solve it. Replied "seek help from others, company and online resources, etc. which I believe is a reasonable answer." But he continued on and asked hypothetical questions such as "what if the person you seek for help couldn't solve it either?" and keeps doing so every time I give an answer.