Missing hex screw on Lily watch - How to repair ?

I'm sorry for the delayed response.  Please reach out to your local Garmin Product Support team.  

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did you ever find a replacement hex screw?  I am in the same boat at the moment and having no luck finding one

In the same boat as well–will reach out to support and update here with what happens

Where did you get it I also have to buy one please 

I believe they are impossible to get and Garmin are impossible to deal with.   I eventually went to a hobby shop and they found me a teeny screw that fits.  It’s not quite as flush as it should be nor the right colour but at leastI can now wear my watch!