Go to your sub-account > Trade settings > USD-M settlement currency. If you haven't made a selection, USD is used by default, so a USDC or USDG balance isn't recognised as margin and your available amount shows as 0. You can't change this setting while you have open orders or positions — cancel or close them first. See FAQ on USD-margined futures contracts. Check the currency. An order can only draw on the currency it's quoted in.

For Spanish nationals (individuals): Format = 8 digits + 1 letter Example: 12345678A For foreign individuals (NIE): Format = Letter (X/Y/Z or M) + 7 digits + control letter Example: X1234567T or M1234567A Found on ID, driver license, or Resident Permit.