Sometimes all the experience and contacts in the world aren't quite enough to tip the balance in your favour. If your CV is a bit thin on the ground when it comes to professional qualifications then consider adding another string to your bow with a vocational course.
Vocational study is ideal because it focuses on practical skills that are of genuine interest to employers. Doing any kind of study as an adult shows commitment to your personal development, which is always an attractive quality. Make sure the course you choose is professionally accredited and delivered by a recognised training provider so that it adds genuine value to your CV.