So sad you getting this experience right now but btw you should be able to trace the transaction using the text in your wallet since you still have access to the wallet, but unless if you want to tell us that you no longer have access to the wallet and of so be if then what will be left of you is to provide all necessary evidence the Atomic wallet really aided an internal hack on user is a wallet.
More also the fact that the who sega is going in such a way that many of those who want to make use of such wallet will be warned beforehand and this is very necessary at some point, but for now you are the only one raising the accusation against them.