I posted this on Reddit back in the day. Use a plastic bag if you don't have the right plunger. Bad for the environment, good for unblocking clogs. Stick a toilet brush inside the bag, a bit of air is good. Secure the top with an elastic band or whatever, you can even use the bag handles tied. Shove it in the toilet and use it just like a plunger, the bag should form a full seal at some point, might take a bit of trying/wiggling but the bag will eventually get a seal because it is variable size/volume. If you are not getting the seal you need you can shove your hand in the bag, it's nasty to some people but in honesty there is nothing touching your hand but the inside of the bag. You can force a seal this way. Now pull. Done. No need to call anyone.