Firefox Connection Issue

Hi,
I have a desktop running win 11, latest updates installed. My av is kaspersky.
When trying to access websites using firefox I am getting the below message. I have tried uninstalling and reinstalling FF and cleared the cache as suggested by search results. I have a laptop with a similar configuration that this works fine on. If I access the same sites through chrome they work fine...

Can anyone assist please?

Secure Connection Failed
An error occurred during a connection to www.instagram.com. PR_CONNECT_RESET_ERROR
Error code: PR_CONNECT_RESET_ERROR

cheers
Rich