Event data change not working - please advise

[PangPP]

Hi,

Please assist as I am having a problem with a BOT EVENT expression not working. This EVENT is set as DATA CHANGE and for Updates (see below) 

Expression is  [_THISROW_BEFORE].[Total Points]<>[_THISROW_AFTER].[Total Points]

The 'expression assistant' test feature shows that the BEFORE number/data is not captured and is the showing the same as the AFTER number/data?

I have configured AppSheet events extension on the google sheet for that sheet

There are no monitor errors (metrics tab) and the bot hasn't run (runs tab)

The test button data shows the event as TRUE so I believe it should have fired

When I press execute (blue button) it works and triggers the process.

However it doesn't work automatically when the data changes after an app sync? 

Thank you.