Please, format your post according to the following guide: How to format your forum posts
In short: please, use </> button to share codes, terminal outputs, error messages or anything that can contain special characters which would be interpreted by the MarkDown filter. Use the preview feature to make sure your text is formatted as you would expect it and check your post after you have sent it so you can still fix it.
Example code block:
```
echo "I am a code."
echo "An athletic one, and I wanna run."
```
Regarding your issue, as @meyay suspected, you installed Docker from snap which is in our opinion is a bad idea. Install it as it is described in the official documentation.
Snap runs packages in a container which is really bad for Docker. I whish I could make canonical stop publishing that snap package.