Hi @Fiona Ellis
Welcome to our forum!
Looks like your issue is more related to Outlook development, please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client. We are not very familiar with the code, the following is for reference only.
As far as I know, currently New Outlook does not support VBA. For the latest developments in New Outlook, see: https://techcommunity.microsoft.com/t5/outlook-blog/the-new-outlook-for-windows-for-organization-admins/ba-p/3929169.
Please kindly understand that many functions are not designed at present. For your experience, consider switching back to the classic version.
To get this feature more quickly, I have found a post in feedback collection website, and you could vote for it. Many features of our current products are designed and upgraded based on customers’ feedback. You can also make suggestions on that website and hope Microsoft will notice this in the future. Thank you for your understanding and support.
Hope this helps!
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