@weenanc: I'm glad to hear that you have found your Galaxy Watch Active2, but I'm sorry to hear you're experiencing this issue. If it has been through the wash then the problem may be stemming from liquid ingress, however you may wish to try resetting the watch via the Galaxy Wearables app on your connected phone. Please check the guide below from our friends at Samsung US to see if this helps.
If the watch continues to boot loop then I recommend reaching out to our Help Desk on 0333 000 0333, or via Facebook or Twitter, where an advisor will be able to arrange for the watch to be inspected and repaired by one of our engineers. If the issue is deemed to be the result of liquid damage then please be aware that a charge will be applicable to cover the cost of the service.