My mother is 83 and has a lot of health issues. She has very limited vision, had a stroke in 2022 resulting in ongoing cognitive decline, and she has a physical disability now so that any able to drive or walk much. Luckily, we’re a close family and so her three kids are all nearby and we do a lot for her which is great because it means she can manage at home. At least once a day, one of us will bring her someone for some fresh air and to do her shopping etc. She’s happy with this setup.
Like a lot of families, children seem to be given specific roles. My sister is the one she’ll turn to her help with things like meals, filling out forms, anything medical. My brother is called first if it’s anything to do with house or garden maintenance, or if she needs drives to places further afield, I’m the one who gets called about anything to do with banking or legal, or if she had trouble with her phone or tv- basically, I’m tech support 
Just to be clear, we all love our mother and do our very best for her.
She rang me this morning while I was at work to ask me for her broadband password. I told her she doesn’t have broadband. She couldn’t really understand what I meant and wouldn’t entirely know what broadband is, but she knows it’s needed for computers. She’s never used a computer in her life and doesn’t have a smartphone- we’ve tried one with her but it was a disaster so she went back to her basic phone that’s specifically designed for older people.
I asked her why she needed a broadband password and she said “I’ll need it for the telly man”. Long story short, her tv provider made a sales call to her yesterday and mum’s take on it is that they’re giving her free tv for a year and she’ll have loads more channels (despite having about fifty million currently and rotating between three constantly). She then asked me if I could take a morning off work next week to be there for “the telly man”. Turns out she’s signed up to a very advanced package requiring the installation of a new satellite dish, and the “free” element is the installation but her monthly bill will go up significantly. I’d imagine the sales people did explain that to her, but she didn’t grasp it. When I mentioned the satellite dish, she got very flustered because she’s terribly house proud and got upset at the idea of wires being run through walls. I also told her that, without broadband, she’d be worse off with the new package because a lot of the service is streaming. On top of that, because of her vision problems and general struggles to remember things, I don’t think she’d be able to adapt to a new tv remote and she gets very frustrated when she can’t get something working.
After an hour-long call with her tv provider where o had to conference mum in to the call as the account holder, I was finally able to get the planned order cancelled and “the telly man” won’t be arriving. Annoyingly, when I explained she didn’t have broadband, they did try to sell her a package 
Key to this is that this is not the first time something like this has happened. Last year, her phone company sold her an upgrade to the latest iPhone along with a data package any 13 year old would be envious of. She mentioned it in passing to my brother, and it took me half a day to get that cancelled.
There’s been a few other issues over the past couple of years. Like her house insurers selling her worldwide travel insurance when the poor woman hadn’t been on holiday for a decade and can’t walk 20 steps.
While she seems to be savvy enough to scams, she seems to think she’s getting one over on service providers when they’re offering her a deal, but she doesn’t realise that she’s not actually getting something for free, but getting more expense and usually buying a product she can’t use. We’ve been lucky so far that I’ve been able to cancel most things before the contract kicks in but there are a few services she’s paying for monthly that she physically can’t use and she’s stuck in a contract and we have no option other than to pay.
After this morning’s call ended, I stayed on the line and asked the tv provider if they could put some kind of flag on her account to say she’s vulnerable and shouldn’t be called. They said no, she’d have to give that instruction.
Mum won’t do that- her view is that it’s her money and her house and she can do what she wants if she thinks she’s getting a good deal. Fine in theory but she then gets herself into an awful state when she’s suddenly faced with not having a phone/having strangers do installs in the house etc.
After the call, I downloaded the app for the provider, used mum’s account number to setup an account and now I’ve updated her setting so that my phone number is listed as her number and so any sales calls she gets will come to me and I’ll shut them down.
I know if I tell her, she’ll be angry. She was very grateful for my help this morning and relieved when it was resolved, but in another few weeks she’ll have forgotten this and she’ll get another sales call and we’re back to square one.
AIBU to do this?
I know it probably comes across as controlling but it’s a mix of a) hating to see how worked up she gets when she realises she’s signed up for something that’s not at all beneficial, and b) being sick of spending hours on the phone to contact centre dealing with this stuff when it happens.