Hello, I ran my experiment online using Prolific to recruit participants. At the end of the experiment, I have the green pop-up window that appears give participants a unique completion code. Some of the participants messaged me saying that instead of that pop-up they got the following error:
However, their data file did get saved and seems that it recorded everything properly. Does anyone have any idea why this error is occurring and how I can fix it? I would like for them to actually receive their completion code for ease of their participation verification.