When you have any text in your email message that cannot be broken into multiple lines then that long text forces your layout to be too wide, which in turn throws off alignment for the entire message.
A solution is to ensure there isn't any text, including links, that are too long and cannot be broken into multiple lines. For example, instead of displaying a long link (showing the actual URL) you should add the link over some text such as "Read more" or "Click here".
This not only fixes the long link issue in your email, it's also a nicer experience for your recipients.
Related article: Troubleshooting email display issues.