If you installed docker with snap:
simple uninstall:
sudo snap remove docker
and to disable automatic snapshot:
sudo snap remove --purge docker
If after reinstalling docker you have the following error:
bash: /snap/bin/docker: No such file or directory
you need to run
hash docker
and
hash docker-compose
Installation instruction:
https://docs.docker.com/engine/install/ubuntu/
Note that if you installed an old version with snap, you should follow the instruction provided in this article.