[2020] Can't get my account back after providing EVERYTHING.

So late 2017 I bought this game, played it and loved it but after a year lost my pc for x amount of time, when it was retrieved my interested found other games.
Now, I don't know what email I used for the account, it is so stupid but I remember changing and then just forgetting to what one, I have been looking on and off for months.
Then I gave up and contacted support providing:

A support ticket that I wrote that was saved on my email before I changed.
Xsolla recipt.
The email saying I bought the game.
Earlier ingame names.

I keep getting the same boring message back, I don't have the money to buy this game again and I really feel, since the support basically asked for me to provide these things that there is no way the account is no one elses but mine. I get that it's my fault, should never have lost the email but the account has sat there inactive since 2018 at this point, I really feel like they should be able to give it back or atleast be more responsive in the support, this is a last shot of hope, what do I do?