Receiving "Response already received" notifications

Question 

When an xMatters notification targets me, I receive it on multiple devices. When I respond to each of them, I often receive another notification saying that I've already responded. Why is this happening?

Environment

All versions of xMatters

Answer

When you receive an xMatters notification, you only need to respond once (even if you've received it on multiple devices). Once you've made an initial response, any subsequent responses will trigger a system notification to let you know that you've have already responded and a further response is not required.

If you have a preferred device to receive your notifications on, want to make certain devices available only at certain times of the day, or otherwise fine-tune the way xMatters contacts you, you can change your device settings in your user profile.