Elias here with Shopify Support. How's it going?
I understand you're looking to close your store, but you've ran into an error with the payment. Based on the error message, there seems to be two separate issues. There's an owed invoice, which is issued when the trial ends, and there's a decline from the card on file due to insufficient funds.
Not to worry, there's a couple of options you can consider for closing your store. You can pay the invoice and close the store, or simply let the store freeze after 3 failed charge attempts. Once the store is frozen, you don't have to worry about the invoice. However, although a frozen store is considered as good as closed, the invoice would need to be paid if you want to unfreeze the store at a later date.
That being said, was there a particular reason you're closing your store? Also, was there any feedback you'd like to share with us?