Thanks all. We know clearing cache/cookies has helped some people temporarily, but it’s clearly not fixing the issue for everyone, and for some of you the error is coming back very quickly.
We’re sorry, we know this is hugely frustrating. We’ve been investigating further today and now think the issue is connected to cookies/browser data building up in a way that can push requests over a limit, which then triggers the 400 errors. We’ve managed to mitigate this for some users, but we haven’t fully solved the root cause yet.
Because this is happening browser-side, it’s very difficult for us to see exactly what’s going on from our end. It would be incredibly helpful if one or two people who are currently experiencing the issue would be willing to jump on a short screen share call with someone from our dev team, so we can see what’s happening in real time and inspect the browser behaviour safely.
Ideally, we’re looking for someone who can do this on a desktop or laptop, as we’ll need to look at what’s happening with cookies in the browser, which is much harder to do on mobile. We wouldn’t need anything complicated from you, and we wouldn’t ask you to share anything sensitive.
We’re mainly trying to understand what page/action triggers the error, and what happens to the cookies/browser data when the error appears.
If you’d be willing to help, please post here or message MNHQ. Thanks again for bearing with us - we know this isn’t good enough and we’re actively working on it.