HRM Pro is not sending heart rates to my watch after open water swims

My tactic is to sit on the side of the lane, ensure the HRM Pro is connected and then start the session before dropping into the pool.

Thus has worked for me as opposed to trying to start everything when in the pool where it failed 2 days on the trot

Hi is there any update from Garmin? Same issue: Fenix 6S Pro and HRM pro. Have both on and connected when I start recording an activity for hockey. Take the watch off, go play, come back, put watch back on, confirm HRM and watch are connected, then stop activity. Shows 100ish calories based on maybe 10 mins HR data out of 90 min activity. Subsequent ‘Download HR Data’ on watch either can’t find the HRM pro or doesn’t change the activity. There are no breaks in heart rate data on Garmin Connect on iPhone, which would seem to indicate the HRM Pro is recording, but not syncing with the activity on the Fenix. I’ve been having this problem occasionally since buying the Pro but it’s been happening every time the last few months  

I was previously using a Wahoo Tickr X that was 100% reliable for offline heart rate recording, but data couldn’t be used by Fenix for load and training calcs, which is why I bought the HRM Pro. Cmon Garmin, you’re better than this!

*** so update to the above:

I see that after a few hours, even though the activity file is wrong, the other Fenix training / load data *does* look accurate: daily load, heart rate and active calories all reflect the exercise actually done (ie extended period of high heart rate). I guess it syncs from HRM to Garmin Connect back to Fenix 6. It’s just the recorded activity file on the Fenix (and anywhere else the activity file is sent) that is missing most of the heart rate data. Bizzaro

I had the issue and removed battery and worked again but suspect didn't close tight enough and had wonky readings.  Took apart and left for couple weeks and got it working again.  It's been working fine for couple month.  Today it is back to not showing hr for swim.  2 days prior fine.  Come on garmin fix the issue.  If your not going to fix the hrm pro then at least fix the optical so it doesn't shut off during swim.  It works fine e in water if tight as shown by aqua jogs.

It's hard to believe that they are still selling the device which doesn't work and apparently they are not able to fix it.

I'm returning my HRM-PRO - not fit for purpose.  Can anyone vouch for the HRM-TRI?  Is it any better at recording and syncing swim heart-rate?

I never had a problem with the HRM-Tri while swimming.  I recently upgraded to the HRM-Pro but I haven't been swimming in over a year.

Hi Garmin, any updates on this? I just bought an HRM Pro and used it today for the first time for swim. It did not record my heart rate.

Take the battery out and replace it after 15 - 30 minutes.  Worked for me.

But you never know when it stops working again, I can't see the pattern.