Hello @FirstNameL77069 ,
I would generally not recommend accessing the main website on a mobile device, as the site (and especially the desktop version of the email builder) is predominantly built for desktop usage. We do have a mobile app for making quick, on-the-go email campaigns and social posts.
Additionally, I'd also recommend doing a browser cache clear, as that is more often than not the cause of issues for devices properly connecting to the site. If you continue to have connectivity issues when logging in on a desktop / laptop device, please let us know and we can troubleshoot further.