Hi Jao,
The maximum positions was exceeded on the public account that the signal provider sends trades to, this is the account that is used for demo users when they have a demo, they are viewing trades from this "public" account. A demo account is only a "Virtual" demo and does not actually have an underlying MT3 demo account number attached to it.
In this instance the signal provider (ubertrading) sent 6 positions to open instead of 2 max positions, on live account only 2 positio ns opened because we auto blocked off the additional 4, they were not blocked off from the "demo" account. The trades were then removed from performance history as it is a true reflection of live accounts.