Instagram API Matching code was not found or was already used

I have the same issue, I guess it's from Instagram I reported an issue from my client panel in developer > manage clients > Report issue. You can do they resolve this issue as soon as possible.

There are a bunch of developers complaining about the same issue at https://news.ycombinator.com/item?id=13178789. I don't think unchecking "Disable implicit OAuth" fixes the issue as I have already tried that and it didn't work.

The best thing you can do is to submit a report to instagram using your client id to put some pressure on their side to fix this issue.