IT faults not being reported to department

I am in a situation where I have a user who does not report their IT faults to me. This user moans to all her co-workers about PC problems, but never reports them to me. When I do go out to her site and look at her PC it works fine. She says she doesn’t need training. She is bad mouthing me to the rest of the company by saying that she phones me every day to report faults, but I never fix them. I have spoken to her line manager who has done nothing. I am the only IT support person in my company. Any ideas? Thanks a lot.