National Deceased Estates (NDE) delay unacceptable

As executor of my mother's estate, I completed all the forms at the bank for submission to their NATIONAL DECEASED ESTATES (NDE) department on 22 February 2022 for my mother's funds to be transferred from her existing accounts to the late estate account. Despite my emails and phone calls to NDE over the last 4 months I am still waiting for a case number, let alone for this to be processed. They have confirmed that they have all the documents required, and, by phone, they told me that they don't know why there is a delay. All they say is I should call them the following week. This is unacceptable.