Leave Champ Select Because of Invite [Client]

I was in champ select and got an invite from a player prior to my previous game. I don't know why it went through, but I clicked accept to see what happens. Everyone in champ select says they left, then the person banning doesn't ban. The champ select freezes for a little bit then I go back to the home page. Turns out I "left" the champ select and got penalized for 3 lp and a timer to queue up.

I shouldn't have got that invite and/or I shouldn't be penalized or even leave the champ select if I click accept. That's a huge bug. Btw this is on the old/current client.