Watch doesnt vibrate for whatsapp notifactions

Hiya,

I have just purchased an apple watch series 8 but I cannot get it to vibrate when I get a whatsapp notification. I purchased one for my partner also and his is exactly the same.

We get the notification of the whatsapp on the screen but no vibrations.

All other notifications that come through on the watch vibrate.

Has anyone had this and do you know how to fix it please?

Thanks