IPhone won’t ring while using apple watch

Notifications appear on your Apple Watch or iPhone, but not both. If your iPhone is unlocked, you get notifications on your iPhone instead of your Apple Watch. If your iPhone is locked or asleep, you get notifications on your Apple Watch, unless your Apple Watch is locked. For more info, see:

About notifications - Apple Support

If you would like to make this suggestion to Apple, use this link:

Product Feedback - Apple

Phone calls on your main SIM number should ring on both devices unless you disabled it. All other notifications are as Javaliga described

I suggest you unpair it and set up again as New Watch