Hi @Rik Boere ,
Welcome to Microsoft Q&A forum.
According to your description, seems that you are encountering issue about Outlook for mobile. Please kindly understand that here we mainly focus on general issues about Outlook desktop client and know little about Outlook for mobile. So, in order to better solve your issue, it is suggested for you to try contacting the in-app support (see Get in-app help for Outlook for iOS and Android) or post a new thread to the dedicated forum for Outlook for mobile.
Thanks for your understanding.
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