I also bought the HRM-PRO from Amazon in December 2020 and it stopped working in December last year. Sent it to Garmin in Johannesburg a week on later they sent me a HRM-PRO. No questions asked about out country purchase.
For the past week the signal/network keeps disconnecting,/disappearing sometimes up to two or three times an hour. Sometimes it comes back after about 7 minutes sometimes it takes hours to come back. Could you please investigate.
@rain_mobile