Just sent a message asking what the male ticket was doing, and he replied: doing something! How should I reply to the message?

You can answer him like this: "I thought you were off today Sunday, and I wanted to talk to you, but I didn't think you might be working." If he is not at work, he will be embarrassed and will reply to you. If he doesn't want to talk to you, he will be ashamed to say it. If he keeps ignoring you, there are two possibilities. One is that he doesn't like you, and the other is that he is really busy, but he won't express it!