As it stands now, it sounds like you have a Canadian Shopify Payments account set up on your store, and so switching your store location also means you will need to switch your Shopify Payments account to a US one; You will need to go through the Shopify Payments account setup for your business within the new region, including entering a bank account that fits the requirements for a US Shopify Payments account.
Does that make sense? If you have any other questions or concerns, please let me know. I’m happy to help.