Why do I have to block someone on multiple devices?

Two times now I’ve blocked someone on my phone but their texts and calls can still come through on my iPad. The Apple website says once you block someone, they’re automatically blocked on all devices. That isn’t my current experience at all. My contacts aren’t synced between the two devices, so it shouldn’t even be able to transfer. And yes, it does say on my iPad when I check the contact, that managed to get through again after being blocked, that they’re still blocked on my iPad. So, I’m getting messages and calls from a blocked number. It should be automatic after being blocked on one device if it’s also clearly still connected to my other devices.