I use the MoonStrike strategy, but it doesn’t work if the strategy settings have OrderSize=0 (take the Buy order size from the main settings of the MoonBot terminal), what could be the reason?

If you set the OrderSize = 0 parameter in the MoonBot terminal strategies, the order size will be set according to the main settings on the main window from the Buy order size slider or from the fixed Buy order size buttons. But the MoonStrike strategy is an exception in this case, and in its OrderSize parameter it is necessary to set an order size other than zero and above the minimum lot on the coin. If you specify OrderSize = 0 in its settings, it will not work.