FNB Share Trading............seek alternatives

Ive been a loyal customer at FNB for tooooo many years, i have a share trading account with them, which i am starting to regret. as a trader, time is of the essence, we analyze charts and have targets set for both our gains and stop losses. I have placed a limit sale, the share price has gone past my ask more than 3 times by over a percent, and i received no feedback on the sale of my shares, the money was needed to purchase shares in another company, so that never happened either, when i reach out to FNB, to find out if my sale went through as i received no update, i am told, they have IT technical issues, same thing happened a few months ago, where i had to eventually sell my shares at a much lower price, just to get out of the trade, this is really frustrating given all the risk we as traders sit with and the Bank sits with nothing but Technical issues!!!!!!!