Mmm, I think we have some misunderstood here. Here is forum of Pokemon Evolution Online (PRO), not pokemon GO.... For the problem in GO, you can submit support ticket to Niantic asking for a gmail change in here https://support.pokemongo.nianticlabs.com/hc/en-us
More information here: https://heavy.com/tech/2016/07/pokemon-go-account-user-reset-deleted-how-to-fix-get-back-gmail-update-pokemongo-fixes/
Locked as off-topic and nothing can help.