Disappointed with the Customer Support, lost Account and Progress

I started playing Diablo Immortal at global launch and invested significant time and money into it. Recently, when trying to log in on a new phone, my account appears to be missing. I can’t recall my battle tag and can’t access the old phone. Despite providing transaction IDs from Google Play purchases, the support team has been unable to link them to my account. I’m not concerned about the money spent but devastated by the loss of time and progress. As a paying customer, I expected better support. Regrettably, this experience has left me too frustrated to continue playing the game ever again.
Thanks for nothing.