Do you also have the problem that you can’t trade leveraged or complex products, at Interactive Brokers?
Then you probably don’t have Complex or Leveraged Exchange Traded Products enabled in your account. To do this, simply go to the top right corner and select Account Settings. Here you can apply for leveraged complex products.
This link will take you directly to the settings: https://www.interactivebrokers.co.uk/AccountManagement/AmAuthentication?action=ManageAccount