Problem with the purchase and the Minecraft Java Edition account

Hello, 

I bought Minecraft Java edition for play with friend on Windows, and when I downloaded the Minecraft Luncher, I have downloaded a second time inadvertently without confirm it. So when I went on the first luncher I installed, I entered my email and my password. Minecraft asked me a Gamertag, I wrote " DiaboloSan31 ". 

But the game told me an other new Gamertag, " Diabolo31Game" ! I closed the luncher and confirm the second luncher. And when I started the Luncher again and entered my account, the game asked me a new Gamertag, I entered " DiaboloTV31 " and it's worked ! But, now, I have an account who work with " Diabolo31Game " and its tell me on the game that I don't have bought the game, I only can play the Demo. And I have the invoice of the purchase.

Thanks for your answer. 

If you can't resolv this problem, I would like to be reimbursed