Hi there and welcome Paul
Can you check that the countdown timer is not functioning? As this can be the issue.
Please let me know
ok, you can set 5 different alarms
Can you check all 5 alarms please and its then likely one of them is set still
ok, turn off R/C mode and tell me if it then alarms please
It is when it gets a time update for synchronising.
Now we see if the alarm sounds again
If there are no alarms set for this, its the firmware that will be at fault, we have ruled everything else out.
I am really sorry about this and you are going to have to return the watch to have it replaced. It will be covered by the warranty if this has not expired, and the replacement will be done at no cost to you.
I am really sorry about this, and if you have problems, or would like any additional information or assistance, please do not hesitate to let me know.
And if you can take a second to rate my service by clicking one of the stars at the top of the page, then submit, that would be greatly appreciated.