If uKit returns the "Unexpected error has occurred" message, this means that we are fixing small bugs and the system is being updated. Try reloading the page and the error should disappear.
If the error is still there after refreshing the page, please contact our Support Team with the details about the device you're using, operating system, browser, and its version. Be sure to make a screenshot of the error with the open browser's console (in most browsers you can open it with the Ctrl + Shift + I command, and then navigate to the Console tab).
For us, it is very important to collect information on when this message appears to our users, so that we can fix any bug that may appear, as soon as possible.