Sometimes, when you purchase an email template from the HubSpot marketplace setting to have the template as a responsive template, is not set by default. If this appears to be the case, this is a very easy fix by simply following the instructions below.
Go to your design manager from the Content tab in your navigation.
Locate your Holiday email template. Sometimes HubSpot does not put it where you would expect to find it, so you might have to search to locate it.
Now, in your cloned file, click on the Actions tab and select “Make Responsive”. It is the last on the list of options.