a lack of basic civility

Over the past year I have had occasion to write the Company which provides a few basic services to my elderly parents.  (A man comes to give my father a shower.  Physical therapist's assistants occasionally come, and more  rarely an actual therapist comes.

Be that as it may, I regard the actual help my parents receive not only as inadequate, but also
as a breach of a promise made to my parents when they were working----not an unusual occurrence today.

However, it is merely basic civility to acknowledge the receipt of a message, an email, a letter. Yet this health care company cannot even manage to say:  "We received your letter and we will consider what you have said. " Neither was any sort of verbal acknowledge made.  Not even, "Oh, yes, I received your email."

That's simply rude.
It can't be excused by saying "We were too busy."  The message being sent to me is that they don't really want to know what I think.  Ahhh, so the customer is always right? ha ha ha-----tell me another one.