Sell orders require users to grant enough allowance for the trade. When posting an order and then subsequently revoking fully or partially the allowance in your linked wallet, the trade settlement process may be impacted. The allowance must be greater than the token amount of all of your open sell orders. If the allowance is insufficient, your trades will fail.
IMPORTANT: every change in allowance incurs a gas fee (like all blockchain transactions). To avoid paying multiple fees, you can place a large allowance that will be sufficient for multiple sell orders.