Allowing Cookies in Firefox (tested in Firefox 82.0.2)
In Firefox, open your browser settings (Firefox > Settings>.
Option 1: Allow all cookies
Search for cookies and select 'Accept cookies and site data from websites (recommended).
Option 2: Add 'app.eduflow.com' to your exceptions list
Scroll to the bottom of the 'Cookies' page and click 'Manage Exeptions'. Add 'app.eduflow.com' to your list and click 'Save Changes'.
Allow cookies in Chrome (tested in Chrome 86.0.4240.111)
Open Settings
Search and find "Cookies and other site data"
Select either "Allow all cookies" or "Block third-party cookies in incognito"
Allow cookies in Safari iOS (tested in iOS14)
Go to the 'Settings' app
Scroll down and click on 'Safari'
Uncheck the 'Block All Cookies' toggle
Troubleshooting
It can sometimes be helpful to restart the browser after verifying Third Party Cookies are allowed from https://app.eduflow.com.