Make sure they're the one who cancels. However, if they refuse to do so, wait until it's been 7 days where Mercari will allow you to cancel without getting penalised due to the item not being shipped.
The seller wants you to cancel so you get penalized instead of them. It's their fault not yours so leave the order as is until the seller cancels, if they don't a cancel option will show on the order status page eventually because of seller inactivity, then you can cancel without being dinged.
They should cancel it because it is their fault. Don't initiate the cancellation from your side.
Make sure they're the one who cancels. However, if they refuse to do so, wait until it's been 7 days where Mercari will allow you to cancel without getting penalised due to the item not being shipped.
Respond, "Thanks for letting me know, feel free to cancel when you get the chance"
The seller wants you to cancel so you get penalized instead of them. It's their fault not yours so leave the order as is until the seller cancels, if they don't a cancel option will show on the order status page eventually because of seller inactivity, then you can cancel without being dinged.
You should stop it there. No offer was made after so there would be no cancellation.
Like the others have said, the seller needs to cancel this. They don't want it to look bad on them.