Why would he ignore me?

I though we had something, but we haven’t talked in weeks.
Then finally he texts me first asking how I was, (I get excited because it was like a sign… that he might maybe still like me) I replied back, and joked around that he missed me, and asked how he was, and he never replied back.

Why would a guy do that, contact you first after so long, text you first and then after you reply he just didn’t reply?
I don’t know what to think.