I recently bought the Forerunner 970 and it has been GREAT until the updates this past week to version 12.70. Now, during runs it does not display my heart rate, and several miles into the run the watch face will go completely black. No amount of touching the screen or pressing buttons fixes it. It will still be recording the run though, and once I get home I can plug it in and then the screen lights up. GPS has also been glitchy to the point that Strava flagged my activities. Totally unusable in this current state. Help please!!!