One of my colleagues seems to have an issue with me. We were friends before I joined the company, he even referred me to the position I’m now in. He actually tried to get me on his team when I had difficulties on my previous team. Something changed and I’m not sure what. 

This colleague is in the same 5-man scrum team as I. He’s avoiding talking to me and seems to have influenced his group of work friends to exclude me. I’m no longer being invited to the monthly dinners we were going on with most of the developers anymore. He recently moved to a different room so he doesn’t share one with me anymore (we have 2-6 developers in a room). 

I asked him what’s wrong. He refuses to tell me. I’ve asked one of his friends whether they’ve been avoiding me. His answer was: “I’m not going to get involved in this.” I take that as a yes. I’ve got no idea what I’ve done. 

I’m trying not to be bothered by these actions on a personal level (which isn’t really working, but that’s not the topic of this question). I am worried about the professional aspect of this. The team is suffering from him avoiding me. Communications are poor and he’s not reviewing any of my code. 

The goal of my question is to get the team communicating again. I’ve considered asking our team lead for advice, but that seems like such a petty thing to do. What do I have to consider when handling this?

I’m Dutch. Colleague in question is Asian. This is in Netherlands.