Some tokens (like USDT L199) do not work when changing the allowance from an existing non-zero allowance value.
They must first be approved by zero and then the actual allowance must be approved.
Navigate to the following contract functions:
https://github.com/code-423n4/2022-02-hubble/blob/8c157f519bc32e552f8cc832ecc75dc381faa91e/contracts/MarginAccountHelper.sol#L24
Approve with a zero amount first before setting the actual amount.
