How do I ask for an informational chat? - 9 months and counting

I sent 12 messages on a professional network and got two replies. This is my first time dealing with any of this. Some people reply with short answers. Did any turn into leads?

I wrote three short lines: who I am, why them and a small ask for fifteen minutes. About one in four said yes.

Follow up with a thank-you and a short update. One of my chats led to a referral a month later.