Why when I click 3v3 tag it don't work?

[dklm]

In arenas when I want to change to 3v3 I click the 3v3 tab.  But now I click it many times and it still won't change.  Same if I go to 3v3 and want to switch to 1v1.  I click many times but there is a pause and then still same tab.

[Grimoir]

I have it also, i needed to click 2-3 times yesterday for it to change the tab to 3v3

[Frozenstar]

Same here.Seems like a bug or something..

[CrowFox]

It's a bug. 
Click on spar and then on 3v3. Works for me this way.