I bought the Lena cup in late July of 2018, and I went to put it back in the pouch today (I sanitized it and left it out to dry). I noticed there’s a little stain on the cup, like a ring of brown (presumably where the blood sat. It might be hard to see which is why I put my finger where it is). I always empty out my cup immediately, wash it out with Summers <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a>, then put it back in. I sanitize it at the end of every cycle too. I’m just confused as to why the ring is there. Does anyone else have a ring on their cup? How do I get rid of it?