Hi Elia,
Do you mean that in the strategy tester you only see 1 trade, or only 1 EA opening multiple trades? Because you can only test 1 EA at a time in the tester. However, if you are only seeing one trade, please check to see that you have selected the correct date range, you have enough historical data loaded and you select ‘Open Prices Only’ as your modelling option.
Thanks,
Ilan