If you have access to a toilet auger (also known as a closet auger), you can use it to remove the blockage. Here's what to do:
Try to hook the debris back out or push it into the larger main pipe. The Cling Film Vacuum how to unblock a toilet without a plunger uk
Flush the toilet. The pressure will cause the cling film to bulge upwards. If you have access to a toilet auger