EPOA Ignored by Home care service

I’m my grandmother‘s enduring power of attorney. I’m also her full-time carer. She is with a home care service provider. And has a level four package. in the last six months my grandmother‘s cognitive capacity has declined severely and approximately two months ago. The home care provider attended our home. I live with her to do a cognitive test which she failed miserably followed by another one with the GP that she also failed miserably, which was also followed up by a brain scan showing that she had severe shrinkage of the brain. The Homecare service is well aware of her current cognitive capacity hence them doing the test himself I find myself in an endless battle with the home care provider. My grandmother was $1400 over budget because of unnecessary travel expenses going to places for the most absurd reasons an example trying to sell a honey extractor and blowup vacuum cleaners are better electrical!. I have made that many visits to the home care provider office to speak to them and politely ask them to stop answering her calls and granting her these trouble requests and they refuse to do so. They also refuse to notify me of these trips I should mention I live with my grandmother to care for her and I find myself cancelling a trip at least once a week they failed to ever let me know she’s made one and I find out when my grandmother’s coming to the door telling me she has a friend coming over. She isn’t even aware who it is when Right At Home call This morning. I was stopped in our driveway on the way to taking her to a doctors appointment with the care coordinator in our driveway arrived for a trip that I had cancelled last Friday to take my grandmother to the doctors which I have to attend with her due to her mental capacity and the amount of appointments we have at the Moment The care coordinator completely ignores me. She disrespect me and it doesn’t seem to matter that I’m her pair of attorney and despite the sacrifice and stress I am going through at the moment caring for my grandmother. I’m getting absolutely nothing from his home care service in the way of help. They keep taking her calls. They keep making trouble appointments for her and they keep disrespecting me. I’m sick of having to ring up and change appointments every week. My grandmother doesn’t even know where she’s going. I received an email from the Homecare provider this morning saying that they will continue to take her calls until I can notify them that she no longer has capacity despite the fact it was the home care provider themselves that came out with a nurse and performed the cognitive test that she ethically failed. I’m waiting this week for an appointment for my grandmother at the memory clinic and I can’t come soon enough. I understand them asking for this information about her mental capacity but surely I have some say as her power-of-attorney on making these decisions or do I not?