Very similar to https://powerusers.microsoft.com/t5/General-Flow-Discussion/Approval-required-multiple-approvers/td-p/69647 but just a little different. All my cases work except case #3. I need a single user to approve out of the 2 users it is sent to which are chosen from a dropdown list in the list form. (InfoPath form)
I am receiving error"BadRequest. The request failed. Error code: 'InvalidApprovalSubscribeRequestAssignedToMissing'. Error Message: 'Required field 'assignedTo' is missing, empty, or contained no valid users.'."

I have 2 columns that I look up email addresses from "Available Team Lead" and "Available Director".
I am using the exact same fields in the "Assigned to" so it should work the same. I tried creating a new case with the same values and it failed the same way. Also on the one that failed, I deleted all the dynamic content choices and then recreated them.

2 cases side by side

If I substitute only dynamic content choice "Requested by email", it works.
What else can I change?