Hi @Johan Groenewald
Welcome to our forum!
It seems that the issue occurs on New Outlook client. Based on my research, i reproduce your issue, this seems to be the default setting for New Outlook, i.e. even if you have resized the pop-up before, after you close the pop-up, the size that opens it again will always be the same size. Maybe it is a good idea to switch back to the classic version, as it could remember your custom pop-up settings.
Please kindly understand that many functions are not designed at present. 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.
Thanks for your support and understanding!
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