If you are looking to change your currency after your first sale, our support will need to make this change for you.
To connect with our support, first head to our Help Center and log into your store.
Once you're logged in, please enter your question in the search bar. Doing this will present you with links to relevant documentation on our Help Center, as well as an option to contact us directly if you require further help:
If you are unable to login, you can choose the "Continue without logging in" option at the start and continue through the same process.
Hope this helps!