Can I change my store's web address (sellit.ge subdomain)?

Your store's web address — <subdomain>.sellit.ge — is fixed and can't be changed from Settings. In Settings → "Store profile" the "Store address" field is read-only: it just displays the address with a "View" link beside it that opens your storefront, and the note reads "Your web address stays the same — only the name changes." Note: renaming the store (the "Store name" field) does NOT change the web address — the subdomain stays the same. There is no way to edit the subdomain on this screen.