This question already has an answer here:
I was trying to play this morning, when I open Pokemon go app, it ask me to confirm my gmail account so I ask to receive 6 number pin on my mobile by message. As soon as I confirmed it, it start from 0, chose your Pokemon,etc. what can I do to have back my account? I was already at level 15. I just use my mobile to play, I don't use any other device, and nobody else use my mobile. I didn't cheat. I start playing in London, I came to Madeira island in holiday's and I will be back to London in 6 days. Thank you very much for your attention.
I've tryed many things to fix it, but nothing. I try to start again choose the same name but it says not available. Does it mean I still have the chance to recover my account?