Okay, so on your profile, on the left hand side, go to 'My Templates' and find that template and click 'view template' and on the right hand side it should have a box that has 'Name', 'Alternate Names (comma-separated)', and 'Description'. Go to 'Name' and change it, then click 'Update' and at the top after clicking that there should be a green box that says: 'Updated template successfully!'