It seems like that your seed or privkey is exposed and you got hacked is more likely than it was on Binance DEX or Atomic Wallet fault. No one can access your wallet unless they got your seed or privkey somehow.
Thats the only reason. OP does not share any wallet address that we can check so I cant know for sure or maybe just a glitch on the app thats why its gone. Or related to internal error on Binance wallet.
If this was the cae then lot of people would have been lost their money and it will become a hot news in crypto space but it likely only OP got this issue so maybe atomic wallet is the problem not the exchange he used to buy coins.