My missing books in Augsburg - horrible hotel attitude

So I lost my newly bought books in hotel(Übernacht Hostel Augsburg) yesterday morning, I came to the reception to ask for help because I thought maybe the cleaning lady mistakenly took it when she cleaned the room so the receptionist should know.
But the reception lady wasn't that patient for my little problem, instead of trying to find a solution or offer some basic comfort, she told me to "pay attention to my own books", "your books are not here, nobody wants your book". So I spent the whole day looking for the book, and ended up went to bookstore to buy the identical book again.
That night I wrote email to the hotel and this morning they found it, it was the cleaning lady put it away because she thought it belonged to a guy just checked out. I thanked the receptionist who gave me back the books (a different person, who is very nice very friendly) and asked her how to reach out to the management cuz I can't resist to point out the attitude problem of that receptionist for I worked in hotel business too, I feel related, she told me the manager comes at four p.m.
Thought I could give them some small advise on how to treat their customers nicely, at least pretend to care about customers' problem ok?
But guess what, turned out the manager IS the receptionist I first encountered. Well, I'm speechless, you win, I'm not coming back to your hotel again tho. Not even an apology ever given for the missing books.
unbelievable.