Can’t pay at convenient store, what happens?

I ordered something at a Japanese store that does not cancel orders and it was mistaken to pay at a convenient store. Also cannot change in how to pay the item. So if you don't live in the country and they can't cancel the order, what happens next? And usually would there be a fee for not paying at the convenient store?

So you are outside Japan, and placed an order with a Japanese online store that requires you to pay at a convenience store in Japan, but agreed to ship overseas?

When you say pay at a convenience store, I am assuming that they require you to pay in advance at a convenience store by printing the payment slip, presenting it at a convenience store and paying in cash.

If that is the case, they will wait for you to pay, and since they will see that you are not paying, they will simply not ship to you. The shop might blacklist you for non-payment, so if you don't try to buy from the same shop again, it should be OK.

But have you tried writing to the store to say that you by mistake chose that payment method, and if you could place another order with (possibly) card payment?

What happens is specified in the shop's conditions of service, to which you have agreed before placing your order.

@AK: Thank you so very much for the quick response and you are correct on the assumption of the process needed to be done via. convenient store method. To answer your question, I have yet to ask them if I can pay using the card method simple because I do not have the funds to buy the items twice. I already made an order for the same product after seeing the mistake was made to pay at a convenient store. But because they can't cancel that order i'd be buying it twice. So I wanted to see what the consequences are if I was to not pay .

@Firas: I have looked into the rules of the site but don't see anything referring to what would happen if you couldn't pay through the store. This is the source: https://shop.asobistore.jp/guide/rule

Again thank you guys very much. I may contact them to see if I can buy using credit card, though I have no use to use this shop again.

They don't ship outside Japan, so after seeing the address, and seeing that you are not paying, they might just consider your order not valid.

They do say that they do not accept any cancellation or change of payment method (looks quite inflexible to me, but I have encountered other shops having similar policies).

It is an invalid order. As said above. They'll realize you are outside Japan and have not paid and they'll cancel/void the order.

Tell them the truth and apologize for not being able to proceed with the purchase.
People make mistake all the time. I am sure they 'll understand.