What could Bill.com do to make their customer service less responsive?

Bill.com bounced a check on me. Their check. One that they wrote to me, I deposited, and then they denied payment on. A) they didn't know they had bounced their own check. B) Attempts to call Bill.com required the use of some chat service staffed by bots, or really incompetent humans, who know nothing and will do nothing. C) The company does not list a phone number on its website - always a bad sign. D) When you find a phone number, it is staffed by people who can only tell you that someone will call you back, but they have no idea when. And on and on it goes. No one calls, then finally someone does days later and they have no idea what to do so they do nothing. No communications - no calls, no email, total radio silence. Need ideas to make this even worse. I'm sure senior management will want to know.