Problem - Crown purchase doesn't work through the game or website – Displays "not logged on" but at the same time as saying "logged on" (top right). 

Solution - 

Cookies being disable for login.strongholdkingdoms.com will cause this issue. Open Microsoft Edge and click on -

1. Three dots in the top right corner
2. Click on 'Settings'
3. Scroll to the bottom. Click on the 'View Advanced settings'
4. Scroll to Cookies and ensure this reads 'Don't block cookies'

Alternatively, you could visit https://login.strongholdkingdoms.com/pay.php in another browser, logging in and purchase Crowns.