Why does Google show in the search along with the main version, mobile?

Question

Google

There is a main version and a mobile version on a subdomain:

site.com
m.site.com

The main version indicates that there is a mobile version:

<link rel="alternate" media="only screen and (max-width: 640px)" href="https://m.site.com/">

The mobile version says that the canonical page is: site.com
But in the main search, Google mixes and shows two versions at once, what to do about it?

Answer 1

There is a form for complaining about search results, you can try to write there . But I would not consider this a problem, I checked the canonical again and which version is ranked by target queries.