M25 suddenly goes cold with me F22, am I missing something?

M25 and I were in the talking/dating stage for more than a month and went on 7-8 dates. Our dates normally lasts from morning to night and we would mainly be talking. Due to how much conversation we had, and his actions/gestures, I believed that we got to know each other very quickly and became comfortable with each other very very fast. Things were going well, but he wasn't able to commit to a relationship now so I left.

This doesn't change how I felt about him and I realised my feelings were still there so I reached out a month later and he was being very reciprocative. He told me he missed me too and kept thinking about me. However, this was cut short and he went cold. I tried to talk to him again, but he told me that he does not want anything to do with me. This was all so sudden and I feel so heartbrokened. Why does he suddenly want absolutely nothing to do with me?