Sorry that this has happened to you. It is very distressing!
Two days after my father died, the nursing home rang me to get me to take all his things out of his room as someone was waiting to move in.
I went up the following day, and they had put all his things in black bin liners and had stored them in a cupboard as someone else had already moved into dad`s old room.
I had paid the previous month`s bill and dad died three days into a new month, so I expected a bill for the three days. Silly me. At the end of the month, I received the usual bill for the month. It had a breakdown of the dates, nursing care, cleaning, food etc., This was very disturbing. I took the bill to the nursing home and showed it to the receptionist ( who usually takes the payments ). I politely explained that dad had died and may be there had been some mistake. She looked at the bill and didn`t know what to say. I asked to speak with a manager and the manager looked at the bill and said they charge by the month and that they still have expenses to pay. She was very cold and hard. I said I am willing to pay for my dad`s care, but not someone else`s. I suggested that she send the rest of the monthly cost to the new resident. She spoke with another manager, presumably someone above her, and came back red faced and begrudgingly took a reduced payment.
I hope you get it sorted out.