Single Post Title bleeds across my left column

I’m working on a blog for a client – the original designers set this up using a Woothemes theme.

Here’s what a single post looks like:
https://www.gartzmantaxlaw.com/90-day-letter-tax-help-irs-notice-of-deficiency/

Any idea WHY my post title is bleeding across the left column? How do I make it wrap?

The code in single.php looks fine to me:
<h2 class="title"><?php the_title(); ?></h2>

Thanks for your help.