Since Tiller uses a 3rd party data provider to connect to and access your bank data you need to allow 3rd party cookies for Tiller to be able to access our data provider's account connection system.
If you have 3rd party cookies disabled in your browser or via some browser plugin or software you may see this message when trying to add or refresh accounts on the Console.
To allow 3rd party cookies for Tiller for Google Chrome
Click the crossed out "eye" icon in the upper right of the URL bar.
Click "Site not working"
Click "Allow cookies"
Alternative, you can manually configure your privacy settings to allow the cookies. These are for Google Chrome, but the same basic steps apply to other browsers.
Open the Settings for your browser
Find the Cookies settings (under Safety Check in Chrome)
Add https://sheets.tillerhq.com:443 as a site you want to allow 3rd party cookies. You may not need the :443 at the end of the URL in some cases.
Refresh the Console and try again.