The answer to 'why is my toilet burst pipe' is that a burst pipe is likely caused by freezing temperatures, high water pressure, or a blockage in the pipe. Symptoms may include water leaking from the toilet, water pooling around the base, or the toilet not flushing properly. Solutions can include thawing the pipe, adjusting the water pressure, or clearing a blockage.
If the burst pipe is inside the wall or under the floor, it's best to call a professional plumber to diagnose and repair the issue. Attempting to DIY a major plumbing repair can be dangerous and often leads to further damage. A plumber has the right tools and expertise to safely locate and fix the burst pipe without causing additional problems.