Do you got this ? Error: Cookies are blocked or not supported by your browser. You must enable cookies to use WordPress.
If you have a caching plugin installed on your WordPress website, chances are that you will experience a “Cookies Blocked” error message while trying to log into the WordPress admin dashboard. I don’t believe the problem is actually that cookies are blocked by your browser.
Some people uninstalled and reinstalled WordPress, reinstalled all their plugins etc.
Here, I only sharing a temporary solution.
When you see this error message on WordPress login screen, just click again the submit button, then it will be login to dashboard.
NB: It is only a temporary solution.