I don't think she's confused. I suspect she keeps calling you to help her do things, because you've rewarded that before. Compare what DS9 suggested and what you actually sent:
Originally Posted by "DS9"
Hi XW. I think it’s best if you arrange disposal of the machine yourself. Regards Dan ‘
Originally Posted by "Dab35 Attempt 1"
I'd call the council and check if they can collect it.
Originally Posted by "Dab35 Attempt 2"
Here is the number to organise collection. It'll cost [x]. It won't be collected on Monday when the buyers move in.
See the difference?
Originally Posted by "Dab35"
Shall I just do it? Is it worth arguing about this?
Good job not doing her task yourself, assuming it is her task. A text that it's her responsibility (if it actually is) doesn't take very long, it sets a boundary, and it takes two to argue--she has to resolve her own anger.