This type of error can block your usage of Tinkercad. If you see this try the following solutions:
-Reload the webpage.
-Clear the cookies and browser cache in Chrome.
If the above do not help, it may be an extension of Chrome that is causing the issue. If the site works fine in "Incognito Mode", then its likely a Chrome extension that is blocking the usage.
To disable an extension, type chrome://extensions in the address bar.