DM'd a girl on GroupMe asking for a phone number, is there any way to salvage this?

I was at a dance marathon over the weekend and met a girl. I talked to her for literally hours (there was so much time to spare) and danced with her for even longer. To clarify, when I say danced I mean in the same group/ circle/ proximity; the event was not suited for slow dancing.

I felt like I connected with this girl, and after the event ended I went to look for her. Unfortunately, I did not see her after it ended and was unable to attain any contact information.

So the only way I was able to contact her was through GroupMe DM because we were in the same group that ate together etc. So I sent her this message:

"Hey this is Bryce from Dance Marathon! I was looking for you at the end of the event but I guess I missed you on our way out. Anyways, it was great meeting you and dancing, and I want to get your phone number!"

She never responded, and I feel as if I messed this up really badly. Is there any way that I can fix this? And for future reference what should I have done instead? Thank you!