Using both canonical and “noindex” tags together to remove a page from Google’s index is not recommended because it can cause confusion for search engines and may not effectively remove the page from the index.
The canonical tag is used to indicate the preferred version of a URL to search engines, and tells them that the content of multiple pages with similar or identical content can be treated as a single page. The “noindex” tag, on the other hand, is used to specifically prevent a page from being indexed.
If you use both tags together, search engines may not be able to determine your preferred version of the URL, or may not correctly understand that you don’t want the page to be indexed. It’s generally better to use one or the other, depending on your specific needs. If you want to remove a page from the index, using the “noindex” tag is the recommended approach. If you want to indicate a preferred version of a URL, use the canonical tag.
Worst case scenario
In a worst case scenario the bot interprets the meta robots information in a way what he should do with the target URL. In that case a meta robots “noindex” can lead to deindexing both – the canonicalizing and the canonicalized page.