How can I solve the problem?
Hi @glowups
Thank you for the screenshots! To confirm, are you only seeing the error message “This store is unavailable” when you try to access the theme editor? Or are you seeing that error even when you are trying to sign into your store admin in general?
Regardless, I recommend reaching out to our authenticated support directly to report this as there may be an issue with your merchant account. To access our authenticated support, please follow this link: Shopify Help Center. Use the chat window on the right hand side to ask to speak to a support advisor.
Hello, the error occurs when I enter the official website, and when I try to modify the theme, all the templates that I attached have the same problem.
Thank you for confirming that! Please use the link I provided to contact our authenticated support for further help troubleshooting this.
Hello, I opened the link for customer service, but where can I talk to support? All options have an explanation or video 
Use the chat window on the right side (desktop/laptop) or bottom of the page (mobile) to request to speak to a support advisor.
Hi @glowups - thank you for the screenshot. If the prompts don’t solve your issue then you can click the blue link in the chat window that says “I still need help”. The chat bot will assist you in connecting with our support team from there.