I’m a first time cup user. I’m having trouble with my cup. I know there is a learning curve and will take a few times to get it figured out. But is there any way to keep my cup from slipping? I’m able to insert it and it stays but when I use the restroom it seems to slip down almost every time. I’m not sure what I’m doing wrong to keep it from doing this. As my period has gotten heavier through the week, it has started slipping more and I can’t seem to get it to stay put. I have the Luna cup.