I encountered a similar problem as you did. However, I managed to resolve it by sending a ZIP file containing only two specific files: “Tippa_week1_Assignment.doc” and “Westernmalaria_Tippa_practical_1.qgis” within the “Tippa_week1_projectfile” folder. I made sure to remove all other files such as the Raster folder, table folder, temple folder, and vector folder from the project file before submitting it. This approach seemed to work, and I believe the issue may have been related to the large size of the initial submission with all the additional folders. I suggest you try the same method, as it might work for you as well.