1 - If your site has lost connection to Patreon this can happen. Using the below steps can force the connection to refresh:
Also, you can try going to WP admin → Patreon Settings → Post Sync and set up post sync by saving both forms. (Save + Done).
Then you can try a manual import to see if the manual import will work.
2 - Yes that sometimes happens and the solution are the steps I posted above.