Shocking backup service for repairs

I purchased a Garmin Vivosmart HR watch in April of this year and purchased a 3 year Assurant guarantee from Amazon, in case there was an issue with the watch. This was done when I was in New York. I am now in South Africa and have a problem with the watch and want to get it repaired and can get no joy out of Amazon, their supplier of the watch, or the underwriter of the warranty. In fact - what I have found, is that the process to try and get this resolved is so laborious and frustrating and it seems that this may be by design, so that I give up and accept this low level of service. I am virtually at that stage now, but thought I would try this platform first. Perhaps I should just throw the watch away and buy something else, from an alternative supplier. Not sure I'm going to be running back to Amazon, for any product with any kind of moving part. Why is it so hard to get customer service from you, Amazon???