If I have changed my name since leaving Australia, does that mean my credit history starts afresh??

When I was born i was adopted but not legally. I was "adopted" (the Maori way) within my family.

My birth mother gave me a name and my parents & older siblings that adopted their beautiful baby sister (me lol) didn't like that name, so they named me but never got it done properly. I grew up being legally known as my birth first & last names, but would always explain why I had two different names and banks, work and income, IRD soon got used to my story and all was good.

I do have bad credit though from being in a bad relationship. Most of my debt is in my birth name as companies went by the name on legal documents. Putting all that aside for a moment - I decided I would finally legally change my name to be the same that my family gave me so I did. I got a new passport number and everything. I use to live in Australia (with my old name) and created one bad stupid debt that I regret and am still paying it off. I want to move back.

My name has changed legally now.. Will my debt from NZ, including the debt with my birth name, follow me to Australia?? Or will my legal name now show up "clean" ??? And show no history?? Some companies will probably think it's too good to be true to see a 25-year-old single mother with no credit history lol. Please help!