The nerds at Google and Apple want you to know when even a single key has matched. The public health people at the NHS only want to tell you when they think you've had a serious exposure, and keeps silent otherwise. That's why you get two sets of mismatched notifications.
It does still mean you your phone has at least briefly been in contact with someone since confirmed positive, so it's not a complete false alarm.
The nerds at Google and Apple want you to know when even a single key has matched. The public health people at the NHS only want to tell you when they think you've had a serious exposure, and keeps silent otherwise. That's why you get two sets of mismatched notifications.
It does still mean
youyour phone has at least briefly been in contact with someone since confirmed positive, so it's not a complete false alarm.