Can I use my old breast pump?

My old medela has been sitting in my closet for six years. I was just going to reuse it but then I was told that medela is self contaminating and that milk gets suctioned back into the box and gets trapped and can’t be cleaned out at all? I just feel bad throwing it away it’s like a $400 product. But I’m fairly certain my insurance or WIC can still provide me a new one for free.