Recent calls list from iPhoneA appears on iPhoneB. How can I remove it?

I do have 2 iPhones.

iPhoneA is for work, iPhoneB is personal.

Recently all my made and received calls on iPhoneB appar on iPhoneA, but not in the other way...

Calls made and received on iPhoneA don't appear on iPhoneB.

I always have had 2 iPhone, mas only recently did this happen...