This is because your web browser has blocked third-party cookies used by the Google account.

Here's how you can enable third-party cookies.

Google Chrome:

To enable cookies in Google Chrome (PC / Mac):

  1. Open a new tab.
  2. Enter this address in the address bar: chrome://settings/cookies
  3. Click on the Add button in the Sites that can always use cookies row.
  4. Key in accounts.google.com
  5. Check the option 'Including third-party cookies on this site.
  6. Click 'Add'.

To enable cookies in Google Chrome (Android):

  1. On your Android device, open the Chrome
    Chrome
    app.
  2. At the top right, tap More and then tap on Settings.
  3. Tap Site settings and then Cookies.
  4. Next to "Cookies," switch the setting on.
  5. To allow third-party cookies, check the box next to "Allow third-party cookies"

Mozilla Firefox:

To enable cookies in Mozilla Firefox (PC / Mac):

  1. Click ≡ (hamburger menu) button and select Preferences.
  2. Select the Privacy & Security panel and scroll down to the Cookies and Site Data section.
  3. Click Manage Permissions….
    • The Exceptions - Cookies and Site Data dialog box that opens will show you which sites you have blocked from storing cookies.
  4. Make sure the site accounts.google.com isn't listed. If it is listed, click on its entry, then click 'Remove Website'.
  5. Close the about:preferences page. Any changes you've made will automatically be saved.

Safari:

To enable cookies in Safari (Mac):

  1. Go to the Safari drop-down menu.
  2. Select Preferences.
  3. Click Privacy in the top panel.
  4. Uncheck the option 'Block all cookies'.

To enable cookies in Safari (iPhone/iPad):

  1. Open your Settings.
  2. Scroll down and select Safari.
  3. Under Privacy & Security, uncheck 'Block All Cookies'
  4. Select 'Always Allow.'