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The status code 301 isn't an error. A 301 is a redirect, which is either Cloudflare or your webserver sending you to another place.

The HTTP 301 Moved Permanently redirection response status code indicates that the requested resource has been permanently moved to the URL ...

HTTP response status codes ; Successful responses. 200 OK · 201 Created ; Redirection messages. 300 Multiple Choices · 301 Moved Permanently ; Server ...

On the World Wide Web, HTTP 301 or 301 Moved Permanently, is the HTTP status code used for permanent redirecting . It means that links or records to this URL should be updated to the destination provided in the Location field of the server response.

Error: Failed to load about:blank, with network status code 301 and http status code 0 - Protocol about is unknown · Issue #5274 · ...

The 301 Moved Permanently status code indicates that the resource has moved to a new location that is specified within the HTTP response.

Status 301 tells you have to fetch data from another url which in your case is /mobile. You need to set user-agent request header to a web browser.

The HTTP status code 301 means that the requested resource has moved, and that this and all future requests should be directed to the given URI.

Learn about the 301 Moved Permanently error, its causes, SEO implications, and effective strategies for implementing and managing redirects ...

301 Move Permanently 是HTTP協定中的一個狀態碼（Status Code）。可以簡單地理解為該資源已經被永久改變了位置，通常會傳送HTTP Location來重新導向到正確的新位置。