That's strange! Have you tried using a different browser or Incognito mode? Let us know if this helps.
I had to try a different browser, as incognito mode wouldn't work either. But having left it for a few hours, it's now working again in Chrome.
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
I had to try a different browser, as incognito mode wouldn't work either. But having left it for a few hours, it's now working again in Chrome.