When people connect with mobile device, it works fine.
But when people connects with desktop to https: / / m. gotosailing. com, I need to forward them to https:// gotosailing .com.
I have tried page rules but not working. Is there any suggestion how to resolve this issue?
You won’t be able to do this with a page rule. If you are a developer familiar with JavaScript, you should try Workers.
However, if I may ask, how big of a problem is that? It seems your website has the SEO done properly. So when I did a site: search for your domain using a mobile profile, it returned results with the m. prefix, while the same site: search on a desktop profile returns the naked domain. So I’d guess most people would enter your website the right way.
Now of course people may come through social network sharing. What you could do is work on your website so that it always share the desktop version, even if the visitor is on a mobile device. This way, other mobile users will be properly redirected, and non-mobile users would get the right stuff.
If your desktop website is already responsive, and your mobile website looks the exact same as your desktop site, may I ask why are you redirecting mobile at all?
I would be more than happy to help, if you are still unable to achieve what you want with the previous posts in this thread- I am not trying to tell you do it another way, simply inquiring why you chose to use the m subdomain when that appears to be the only difference between your two website versions.