Starting Coliseum Tier 4 results in no button freeze

I'm era level 50 so I have previously cleared levels 1-3 so I'm starting the current ATST Coliseum at Tier 4. 3 tries have resulted in the same no button freeze that has been widely happening. But this time there is no mid battle freeze nor is it random when it happens. It's at the beginning of battle and it happens every time.