Flags not showing

Hello,

I have a question about this plugin.

The country flags are not showing on my website https://kiteboardschool.nl

On the English version of my site the flags are showing. https://en.kiteboardschool.nl

I have the exact same installation and settings.

How can i resolve this problem?

Thank you in advance for your help.

Best regards,

Thijs

https://www.ads-software.com/plugins/language-bar-flags/