I assume you know for sure his phone isn't lost, he's not in the hospital or on some international trip, and he's not dead or in a coma. Those reasons could innocently (although dramatically) explain his non-response.
If those are not explanations, then follow the rule of three.
1) If he completely ignores you ONE time, it may be anything -- a distracting or inconvenient situation for him, his phone isn't on, etc.
2) If he ignores you TWICE, he may be texting with a lot of people at the same time and he became overwhelmed and put way down on the priority list for responding -- so low you never received a response.
3) If he ignores you THREE time, that's intentional, it's a trend, and he's trying to tell you he isn't into you. Forget this guy. If he plays games and doesn't give you the respect of a reply, he's trying to telegraph to you that you feel more strongly about him than he does about you. So sorry.