Heart Rate reading keeps stopping on GWU perfectly fine on GW6C

[Blu-Ray]

So i have a GWU and a GW6C. I've noticed the heart rate doesnt always record on the GWU. I do not have this issue with the GW6C. Both have very similar bands and both are fitted the same.

In the images attached for the same type of workout, GWU drops the heart rate recording often during the work out (grey dots in the HR line). While you can see the GW6C is continuous through out the work out. I've been through the past 4 weeks of workouts and noticed GWU is always doing this. I have yet to see it on the GW6C. I thought GWU was the better watch if the two?

Anyone else having issues with the heart rate readings like this? 

[Samsung_Moderator]

Thank you for reaching out. I can certainly understand your concern with your Galaxy watch Ultra. In order to better assist can you please provide me with the following information:

1. Are both your watches Bluetooth, LTE, or one of each?

2. When you started noticing these symptoms, did you recently have an update to the watch or the Samsung Health app?