Being technically excellent in your chosen field does not automatically transfer into being an excellent manager of people. 

In fact, most technically gifted people struggle with the personal relationships which an effective manager must have.

Do not fear, all is not lost - there are ways and means of enhancing your skills without getting too bogged down in courses, training days and hours of endless reading. This article is probably a good starting point if you want to hone your skills as a manager and in turn boost your team's productivity.