The following feed started reporting Error 403 on 8/19: Vinted Engineering
The feed is well-formed according to w3c: Feed Validator Results: https://vinted.engineering/atom.xml
Seems like a newsblur-specific failure because it still updates fine with Feedly & Inoreader.
Getting a 403 means the feed server is actively blocking Newsblur.
Samuel might reach out to them when he sees this, but it might be beneficial for you to reach out to them as well.
Thanks, I just wrote to the Vinted support people.
These 403s keep popping up for Cloudflare sites, months after the initial server migration, and the forum has threads about feeds not updating that haven’t received as much as an acknowledgement. Yet ingesting feed updates is the most core functionality for any customer.