TDA, and my broker Questrade Canada are all short sellers.... I suffered the same problem as you. Questrade won't allow me to buy on line, ( I can buy through calling them ,but they would charge $450/trasaction+ $45/order through desk +$10 / trading fee. .. If I could buy through online, then I sure would  buy more as Pizza boss did....geez)

All these shorties are shameless, wish Stevee could find out some solutions.......,