Clergy are expected to work to high standards of professionalism and integrity. Sadly there are sometimes occasions when they may fail to meet this high standard and you may be inappy with their behaviour. In the first instance, it is usually best to try and address concerns with the priest directly. If this does not work, or you don't feel happy to do this, then the rural dean or archdeacon may be able to help resolve matters.
If these informal routes are unsuccessful, there is a formal complaint mechanism, which involves making a complaint under the Clergy Discipline Measure (CDM).
The Church of England website has details of how to make a complaint.