Apple Watch move goal is minutes instead of calories

After doing more research, I think that I've confirmed that I could be right. It appears that you would need to contact Apple support to get the age changed:

Update the birth date associated with your Apple ID - Apple Support

More info about Move Goal in Minutes for 13 and under:

See activity and health reports for family members - Apple Support

I'm guessing that this watch was being used with Family Share.

I did some reading yesterday and couldn't find anything pertaining to undoing the <13yo "minutes vs calories".

A couple thoughts that I have:

1. The age of this user according to the Apple ID that you created, required a birth date, didn't it? I feel that the birthdate is still being considered and the OS could be preventing the user from manipulating their age (i.e. The watch doesn't know who is pushing the buttons).
2. You might figure out that the watch will need to be reset if you can't change that birthdate. You might even need to create a whole new Apple ID to set up this watch for 13+. Use caution, doing so will likely allow the user to have full access to anything and everything.

Hopefully you'll get this figured out ;-)

Are you sure you're not looking at the Exercise goal? To the best of my knowledge, the Move goal is always calories and there is no way to change that. Conversely, the Exercise goal is always minutes and can't be changed.

Change the Workout Goals on your Apple Wa… - Apple Community