Daisy Chained Thunderbolt Displays quit working

I've been running dual Apple Thunderbolt (27") displays with no issue for years. Now all the sudden only one will connect at a time. MacBook Pro 15", 2016, with Monterey 12.7, in clamshell mode. Each display works fine if individually connected but when I daisy chain one it will not come on. I reset the SMC and VRAM and that made them both come on but as soon as I walked away for 30 min and tried to bring them up just one comes back on. I've tried everything including swapping the order of the daisy chain. Am I missing something. I even tried a newer Apple MacBook Air and got the same result. Could it be the apple thunderbolt to usb-c adapter?