If you're getting "payment unsuccessful insufficient funds" as a payment error, then you would need to ensure you have enough in the bank account to cover the converted amount. Your credit card may charge an additional fee for the conversion, which could also cause an issue. Your best bet here would be to contact your bank as the error you're seeing is the only information the bank provides to Shopify.
If you're using a debit card with credit card capabilities (i.e. Visa Debit), then this issue most likely because the card issuer has disabled one of the following transaction types:
If the card does not work, then you would want to look into using a different credit card or using Paypal (if it is eligible in your region).
Let me know if you have any questions.
Is your bank account in USD or a different currency? Our systems charge in USD so if your bank is set in a different currency then it is possible that the conversion costs may be playing a factor. In addition to what I've mentioned above, debit cards with credit card capabilities are not supported by Shopify. While they may work with our system, we can not guarantee that it will continue to work, nor can we help troubleshoot if an error comes up. What this means in relation to your question is that a prepaid debit/credit card "may" work for the one time purchase, but I can not guarantee that it will as we would recommend and only support using a credit card issued by a bank with a line of credit. If based outside of the United States then you'll also have access to using Paypal to pay for the monthly subscription fee.
I am in Oklahoma so I am using USD. On the other hand I am not using a credit card so that is just something that I need to acquire as a buisness owner. Thank you for your reply it was very helpful!