First, log in to your Luniistore™ account. Then, click on the round-shaped icon in the top right corner and click on My Account, then click on the displayed flag/country (see screenshot below).
Finally, change the country using the drop-down menus (see screenshot below) and click on Confirm.
It is also possible to change the country of the Luniistore™ without logging into your account. Here's how: open the Luniistore™ and then, before logging in, click on the country tab at the top right corner to select the country of your choice.