Round I have just bought off my cousin, I was collecting for thr first time two weeks ago old bird comes out & says who are you I tell her & that I will now be doing the windows she said I see you put the price up I told her I was sorry I must have put the wrong slip through the door so she paid £1 less also gave me a spiel about my cousin being trained to her liking :
, I said to my cousin that he noted down the wrong price for that house he said no & that she had tried it on before ...next clean is 6th oct she will be getting charged a quid more than she should have paid last time & if she don't like it bye bye
She could have the onset of alzheimer's disease and genuinely doesn't remember the price going up. Alzheimer's disease starts by the older ones forgetting what has recently happened, but their memory is still sharp (perhaps even sharper) regarding things that happened a couple of years ago. Sadly, as the disease progresses, their memory goes back further and further in time.
You can't always tell as they realise something is wrong but they mask it to begin with - tell tale signs are aggressive reaction just as you described. Stand your ground politely and explain that she must have forgotten. Don't take it personally.
If she has got the disease, then life is going to be shorter and not much fun later on for her, so perhaps a little empathy and pity may not go amiss. If she hasn't and is trying it on, so be it.
It would be interesting if she remembers who you are next time - there is a very small line between them recognising you or the job you do. You will need to be very observant to distinguish between them.
We have lost several customers to the disease over the years as well as me loosing both of my parents to it.
Spruce.