I'm trying to change the email on my Plarium Play account (Raid: Shadow Legends). I'm the original owner, I have purchase receipts (weekly gem pack, recent champion pass), and I know the approximate registration date +- (July, 2019).
I've contacted support several times. Sometimes I get no reply at all; when they do answer, they say the country of registration doesn't match. The problem is that when I created the account, I was traveling and likely using a VPN, so I don't know exactly which country was recorded.

I've provided receipts as proof of ownership, but they keep focusing on the country. Right now I'm contacting them from a different Plarium account because I can't access the original one. Has anyone dealt with this when trying to change email? How can I get them to accept the payment history instead of the geo‑location? Any advice would be appreciated. 

Thanks!