If you are seeing an "Error connecting to WordPress" notification either when trying to connect your site or after connecting your site it is likely that you have a Jetpack website.
If you had a Jetpack enabled WordPress.com website before you tried importing your blog to Anchor, you won't be able to import your blogposts. You may see the following notification:
If you switched to a Jetpack enabled website after connecting to Anchor, you won't be able to import your blogposts either. You may see the following notification:
You can end up with a Jetpack site if you do a standalone Jetpack install.
Unfortunately, at this time we don't support Jetpack, but this might be something that we can explore in the future. Be sure to submit a feature request if this feature interests you!