Stranger enter our team

Demigra

As you can see, your teammate must be lying. Its impossible for one to enter the team without even receiving any invitation. If you think this is getting serious enough, try contacting the ICS (Ingame Customer Service) To prove if it is either a bug or not.

Crixce

I’m assuming that you were in classic when this happens. Because you can que with 4 players for classic.
This must of happened... you had 4 people in your group. When the 5th person was added to your group, the leader already que for the match. So when the 5th player joined your group they were not in the que for the game. They missed the que up and was left out of the game.

iri

Or maybe, someone invited Irine by accident. Sometimes it happens to me. I invited someone (let's say his name is Alpha), but when I press the invite button, it's someone below him who gets the "invited" mark. Then I need to scroll my friendlist and the problem solved (when I invite Alpha, he has "invited" mark). It happens many times, I don't know if it's a bug or just my phone.

Vymonchyyy

you said its ranked right? you cant start ranked match with only 4 ppl.. if that is really a ranked match, obviously all the member would know when you start matching up, it means you are in a team of 5 ppl.. someone invited this irene.. except if its classic match,its possible that you start with 4 ppl, and get matched up with solo irene..

erbolgwapa

I've had this experience before. I was playing with my squad- 5 man team in Classic. We entered to find a queue but when it was time to pick heroes one team mate was left behind. Our wifi was stable so there's no  issues on disconnections. Strange thing was in his screen it said that he was kicked out by on of our teammate. It happened twice.