Just got a new battery and it won't even light the first light, or anything. Is there something to reset on a mavic battery or did I just get a dud.
Any help?

What is the light status if you press the button once? Have you tried to charge it?

Assuming when you said "Just got a new battery" that you already own a mavic and know how to work a battery, so we don't have to go down with what DJI Diana said.
If you hold down the button on the battery for 10 seconds, does it power on? Double check you've let it charge for 3 hours.

If all is negative, DJI sometimes does ship duds.  You may just be unlucky. Send it back to them, explain it and you should get another one.