How to retrieve the original number?

Hi,

I have a question about retrieving someone's mobile number after they've called you. I met a Chinese girl a few days ago, we talked for a bit and exchanged numbers. She suggested that I type my number into her phone, then she called me, her number appeared on my phone, I saved it and went on my merry way.

Problem is, when I saved it, I decided to delete the initial 2-digit prefix and replace it with the usual 0 digit at the front. Then later, when I tried calling her, an English girl with a different voice and name answered, claiming to have no idea of who this Chinese girl was!

I now see it was a mistake to edit that phone number, but I can't remember what the original 2-digit prefix was. Not +44, because I tried that and it was the same result - the English girl again. Should I try the Chinese 2-digit prefix, +86? Or is there some way to retrieve the number that originally appeared on that first day?

Many thanks for any help.