Problem with betrayal mastermind fight

So I have been playing this league and finally got enough intel to unlock the mastermind fight after many syndicate members killed. I enter the mastermind fight and progress through a few steps of the fight. I get to a phase were I need to kill minor members of the syndicate. I kill them and I think there was a Catarina line of text pop up in the chat and my whole game freezes.
I assume that it is supposed to happen maybe similar to how the game freezes when certain maps are influenced by shaper and there is a shaper voice line to listen to while the game is frozen for a moment. So I wait for maybe 20-30s or so while the game is frozen and it kicks me to the login screen. An error message pops up, I dont remember exactly what it said but roughly it was "You need to be logged in to preform this action".
When I log in again I did not think it would be a big deal and that I could just use the rest of my portals to finish the fight. But all the portals were missing and my whole progress for the mastermind on betrayal ui was reset.
I am not really sure what to do. If I grind all the way back to where I was this problem might just repeat itself and I would have just wasted many more hours.
Has anyone else been experiencing this problem and have found a solution?