Stop your brother printer from providing toner information to your Alexa device (dot, etc).

https://help.brother-usa.com/app/answers/detail/a_id/172810/~/cancel-enrollment-%28amazon-smart-reorders%29

Brother printers provide ink status to any network device, so your Alexa device just has to ask. Turning this off is a bit convoluted; it’s simpler to get rid of any Amazon device from one’s home.

Update. The directions on this page are obsolete. I think it’s not possible to disabled this for an alexa device now.