Spanish National applying for business visa in Hong Kong

Hi, I recently received an M with the assistance of an agency in Hong Kong. I have been provided an invitation letter from the company inviting me to visit but the agency did not accept it and said the invitation letter had to be from the Chinese government. Is this true? They faked an invitation letter for me and applied for the M that way and I ended up only receiving a 14 day M when I needed a 2 month one.