The same issue is happening for me as well!

LSAC just sent an updated email and they are trying to fix this issue. It gives those who chose the test centre option to change it to the remote exam after the problem has been fixed.

I’m having the same issue. Once I select the time zone and test date, it says no availability found. I called the Prometric phone number provided by LSAC in their scheduling email and I’ve been on hold for 25 minutes.