Take it as a sign that you've made a mistake. Try to change the topic to something more positive and light - hearted. For example, start talking about a funny movie or a cute animal you saw. And learn from this experience not to share such inappropriate content in the future.
Stop telling those stories. They are clearly not well - received.
One way is to be assertive. You can say 'Your laughter is inappropriate and disrespectful. I don't appreciate it.' This makes it clear that their behavior is not okay.
Well, perhaps the girls have a different sense of humor than you expected. But in general, stories about such private parts are considered vulgar in most social settings. You might want to focus on more positive, friendly and appropriate topics to share with them, like interesting travel experiences or good books you've read.
Maybe they find your stories inappropriate or vulgar. Such topics are often not considered proper in polite conversation.
You could start by having an open and honest conversation with her. Let her know how you feel about it, whether you're okay with it or not.
If you're curious about 'ghoster', you might try to drop some hints in your next stories to see if they'll interact more. For instance, you could ask a question related to your story content and see if they respond. But don't push too hard, as they might be someone who prefers to stay in the background.
You could start by simply saying thank you. A simple message like 'Thanks for adding me to your private story!' shows your appreciation.
You could just ignore it. If you don't want to engage with your ex, then act like it didn't happen.
You could try not to overthink it. Just keep living your life and posting your stories as you normally do. Maybe they'll come around and start texting back when they're ready.
This is a very embarrassing situation. First, you should try to stay calm. Immediately cover up and remove yourself from the situation as gracefully as possible. Then, you might want to reflect on how such an exposure occurred in the first place to prevent it from happening again.