It appears that in Garmin the Connect web Personal Records (and I assume the app) there is a customize list menu. The 1 km & 1 mile distances are not selected and so (it seems) that you keep getting prompts for a new record until you accept/decline THOSE records. I selected those two distances to display and accepted those records, and it stopped whining about my new 5k record.
This is a bad UI design. I am fine with not automatically displaying those distances, but don't break the user experience due to the default settings.
