Yep, as slymeat says, if you had placed the order for 30 days or anything more than 1 day, the remainder of the order would still be in the market and you would only be charged more brokerage if the amount of the remainder of the sale pushed the order into a higher price bracket. If it was Commsec and you've got their cheapest brokerage, you would have been charged $10 brokerage for today's sale, and then an additional $9.95 for the rest once the proceeds exceed $1K. If your broker was NABTrade, you would be charged $14.95 for today and nothing when the rest sold, because $14.95 covers up to $5K. If Selfwealth, $9.95 for today, then no more when the rest sold. I haven't used Westpac for share trading.
But as you point out laoshi, you placed the order as "good for the day" only, so the remainder of the order has been cancelled and you have paid the full brokerage charge on the sale of one share for less than $1. Lesson learned. Don't place orders that are only good for the day on low liquidity shares, or this can happen. I have a couple of trading rules. One is I NEVER sell "at market" unless it's a very high liquidity company like an ASX20 company, and I don't often buy or sell shares in ASX20 companies, so basically I never sell "at market", I always set a limit price. My second rule is I always place orders for 30 days so if something unexpected happens I can amend the order on a subsequent day rather than get caught having bought or sold a paltry quantity of shares. Third rule is to review all of my open trades each day to see if I'm still happy with the price points. Years ago I was caught out once with a buy order I left in the market and forgot about and they had some bad news and my order went through three weeks after I placed it at a price that with the benefit of hindsight was too high. Thing was, I read the bad news, and didn't realise I still had the buy order in place until it triggered the following morning. Lesson learned. Every night I check what's gone through and what's still open and I then catch up on the latest news concerning those companies and make a call on whether I'm still happy to leave those open trades in place at those price points. I often amend the prices or cancel orders overnight. But if you don't set your orders for 30 days (or however long your broker allows) you don't get those options. That's why I never go for the "good for the day" trades. It closes down your options. You can cancel open trades overnight if you want to, but you can not reinstate cancelled trades without paying additional brokerage.