Hi @Andrew Evans
According to your description, it seems this issue is related to your Teams client.
It sounds like you may need to update your desktop version of Microsoft Teams to the latest version. The background blur and custom background features were added in a later version of Teams. You can check for updates by clicking on your profile picture in the top right corner of Teams, then selecting "Check for updates."
If an update is available, follow the prompts to download and install it. Once you have the latest version of Teams, you should be able to access the background blur and custom background features.
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