It has become very dried out and the leaves are falling off, as are the flowers.
I Have an Azalea That Is Not in Good Shape
The first question is how old is the plant? If it's newly planted, these symptoms could be caused by too little water, or too much water/insufficient drainage; too much or too little light; or placing the root ball too deep in the ground. Here's an article with general tips on transplanting: https://www.gardeningknowhow.com/plant-problems/environmental/learn-how-to-avoid-and-repair-transplant-shock-in-plants.htm
If you've had the plant a few years, you could be looking at any number of problems. You'll need to consider light and water (plants that turn brown all of a sudden often have insufficient water) and look for bugs and disease. Here are a couple of articles that will help you analyze your problem: https://www.gardeningknowhow.com/ornamental/shrubs/azalea/azaleas-noteworthy-shrubs-for-any-garden.htm