I have an experiment that goes Qualtrics > Pavlovia > Qualtrics. The participant number recorded into pavlovia does not match the one recorded into Qualtrics when data is downloaded. Qualtrics is set up to generate a random participant number for each participant so I am fairly sure they are typing the correct one into the experiment.

How is your experiment supposed to work? I just had a go and I kept being shown multiple non-clickable Pavlovia links with different random numbers for each item. That doesn’t sound intentional and you shouldn’t be needing to ask participants to type in numbers manually.
here is the link to the external portion via pavlovia. The issue we are encountering is participant and session number entered at start do not match zip file downloaded.