Being threatened with sending back and non delivery of parcel

I've been running a small home business on the side for 10 years and have use Fastway many times with no problems the previous driver really went out of his way to give the clients the best possible experience. This is no longer valid thought this company now uses a Courier that is rude, and if one does not conform to his demand he threatens to not deliver your package, if asking his name he refuses to provide it. he then gets his friends to phone the next day to threaten with the package being sent back. when trying to contact the company you reach the switchboard witch then disconnects you after trying every single option. Trying the WhatsApp contact us on the website, it asks you questions and then tells you to hold the line with no reply since 15h00 yesterday.