UBS long position liquidated

I found out only now that Ameritrade used the short sale of UBS I made on 19 February to liquidate my long position for the same quantity. This means that the UBS shares I bought on 16 June 2007 at USD 61.69 were effectively sold on 19 February at USD 33.6901, with a loss of 45.4 % in 248 days.

The limit of USD 28.91, at which I had intended to buy to cover my short position, was reached on three occasions today, at 14:22, 14:24 and 14:39-14:40 EST. As I was out when the email of Ameritrade advising me of the inability to execute my order to buy to cover arrived at 13:58 EST I was unable to buy UBS back at 28.91, which would have had the same monetary effect as holding the long position and carrying out the short sale and purchase to cover as I had intended.

I have now placed a limit order to buy UBS at USD 28.91, roughly the equivalent of CHF 30.