Hello! coBlock run parallel question!

Hello I am a teacher who teaches students in Korea.
I have a problem with coblocks coding with run parlee.
Problem: If I try to execute 3 commands simultaneously with add task on the run parel, how can I solve the problem that does not happen the 3rd time?

Hi! Could you please share us a link to the scene that does not work as expected? Or screenshot your CoBlocks code. Thank you.