Why so many documents?

I requested banking details for deposits and investments to be changed. I was told to complete forms and sent proof of address, proof of banking details and certified copy of my id. Being a 70 year old lady finding it difficult to walk, it was challenging and I had to take time off from work to do so. Afterwards I was informed that my phone number is not the same as what was on my record. I have to re do all of the documents with an additional affidavit confirming my phone number. Although I told them to leave it as is, I feel that they should be a little bit more relaxed with the phone number since I could provide them with my old number,