HELP! Direct message not working!

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Hi! I created a direct message feature fashioned after the Medical Centre app shared a few months ago. The feature uses row owners with the emails of the message sender and the message receiver. It was working fine and now it’s not. I haven’t touched the app in a couple of months, so I don’t know why it’s now not working. The email of the message receiver is no longer populating into the sheet. So, when a message is sent only the sender can see it. Help! I have people paying 4-5 figures to be on this app!

Can you record a video of this happening and share it with us? And tell us how to try this in the app ourselves?