citizenship-change of name
 

Can anyone please help me with the following questions ?

Situation
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I have my name as Choudary Amir Mehmood on my Birth Certificate and on Education documents and Amir Mehmood on Passport and Identity Card, Visa, and all other documents.
Before coming to Australia I made Change of Name certificate from Pakistan and submit it to Immigration Department.
Few months ago I lost change of name certificate and reported it to government website.
Now, I am eligible for Australian citizenship.

Question
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1. Do I need the change of name certificate as after coming here I have not change my name and the department already have all the information related to previous name?
2. If I do need the change of name certificate. Should I made it Pakistan or Australia?

Thank you in Advacne