Hi @Robin Barber ,
According to the image you provided, I didn't find a relevant setting or group policy, so I think this issue should be related to your Microsoft account settings.
You can open Windows Settings and click Accounts, then click Email & accounts.
On this panel, you can see your Microsoft account. Now you can click on the account and check if you can edit the option of your Microsoft account. Then try modifying this option and chech if this work for you. Something like this screenshoot bleow:
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