I have a Samsung Gear s3 smartwatch and just upgraded to Samsung Note 10 from Samsung Note 8 a few days ago.
My smartwatch does not ring anymore when I get WhatsApp calls. Although I see a green icon on the smartwatch when I eventually answer the call on the Note 10 phone.
If I connect the smartwatch to my old Samsung Note 8 which I still have, whatsapp calls still ring on it and can be answered.
Version of Software on Watch are below:
Tizen Version: 220.127.116.11
Software Version: R770XXU2FTD4
Samsung Note 10 has below on software:
One UI Version: 2.1
Baseband Version: N970FXXU4CTE9
If it helps, my location is Ireland.