Stroop task assertion error

Does anyone know what this means? My practice trial works fine but every time I continue to the main trial it goes on for a little bit then stops and that error keeps appearing, does anyone know how to stop this from happening?

Please could you show how you are setting the colour in your main trials (and especially how it is different from your practice trials)?

Do the colours have to differ from the practice and main trial? I’ve used both red, blue and green for both.

No they don’t have to differ.

Okay thank you, this is how I’ve set it out for both practice and main trials:

The main difference I can see there is the position of the cursor. I would move it to a cell containing data. I note that the colour in the row it’s in is red, so that could be the issue if the error always occurs on that row.

Otherwise, how are the values used?