Phone jack doesn't work - My responsibility?

[Jenna Stonecipher]

My tenant just texted me that she recently purchased a router for her internet. When she plugged it in, she discovered that the phone jack doesn't work. I didn't think to have the phone jacks tested when I bought the place... I don't think I have ever in my adult life used one.

Is getting the jack fixed my responsibility as the landlord or the internet company's responsibility as the provider?

I should also note that she lives underneath me in my triplex and is a relatively new tenant. It's a B neighborhood, and I'm nervous about having tenant-related issues so close to home. Thoughts?