Pavlovia pilot data not saving on server

Description of the problem:
I am working on an online study using jsPsych and want to host the experiment on Pavlovia.
I managed to set up the experiment to run online and am currently piloting it. All works fine until the end of the experiment when the recorded data is supposed to be sent to the Pavlovia server. A .csv file of the data is saved to my local system but not on the server. The final screen stays with a message saying “Please wait a moment while the data are uploaded to the pavlovia.org server…”, but then nothing happens anymore. In the console, I get an error stating “error: session unknown”.
Also when closing the session, the information about Piloting sessions on my experiment page remains unchanged (completed= 0 (%); aborted= 0 (%); last session: --).

Is this how it is supposed to be when running experiments in Piloting mode? Or am I missing something?

Thanks for your answers!

Best,
Mutzkey

When piloting, no data is saved on the server. A file is downloaded locally instead.