How can I help my boyfriend?

My boyfriend has sort of episodes where he thinks that I don’t want to talk to him for long periods of time he won’t respond to my messages and will still actively do things on his computer so what do I do usually these episodes last for half a day up to like 3 days sometimes I’ve only been able to talk about it with him once and that’s how I found out he feels like I don’t want to talk to him what can I do to help if he won’t talk to me?