The two words don't go together.  "My" is first person possessive, referring to personal ownership by the speaker.  "Team" is a group working together with a shared purpose. 

The moment someone says "my team", that person is setting themself above the team and apart from other teams.  If they are above or apart from the team, they are not part of the team.  If they are not part of the team, it's not their team.  "Our team" works.  "My team" does not.

This is much more about attitude than semantics.  "My team" is a signal of silo thinking.  We've seen too many leadership teams that are not really teams, but, rather collections of individuals forced to meet together.  We've seen too many of those leaders that refer to the members of their division or function as "my team".  It's not their team.  Even if it were, it's not the right team.  The right team is the entire cross-functional, cross-divisional organization working together with a shared purpose.

Don't put up with the semantic difference if you care about your organization as a whole.  (Yes, "your" has the advantage of being both singular and collective.  In this case, I'm referring to the collective.)