Question about seller canceling order...

Bought an item... came in the mail. The same day it was delivered, seller canceled the order and it was refunded back to me. Thought that was weird, but whatever. Then seller dm-ed me privately next day and is asking me for the tracking info for my package and saying she canceled the wrong order. Should I give it to her? What happens now? Just making sure I'm not falling for any kind of fishy business. Is mercari going to re-charge me?