This is either cause of a compromised private key (someone stole your seed phrase) or an active ‘Unlimited Smart Contract Allowance’ approval.
1. Go to **revoke.cash** or Etherscan Token Approval checkers and immediately strip approvals for your address.
2. If the draining continues, your seed phrase is permanently compromised. Abandon that wallet instantly. Do not deposit any more gas tokens; write off the balance and configure a brand-new, sterile seed-phrase environment on a safe hardware module.