Garmin x40 appriach watch (Jericho OX2)

This worked until recently when the strap broke and I lost it outside. I found it about 10 days later and plugged it in to the charger. It blinked briefly to say it was charging and then went blank. Since then I haven't been able to raise a sign of life from it.

I will keep the charger as I have another identical watch and forever misplace the charger so it's useful for me to have 2.

I think it's beyond repair but if you are more technical than me (not hard) please take it and have a go!