Hi @DG ,
According your description, I did some research and found the following links which might be helpful:
Change email notifications
How to create custom Gmail alerts on any Android device
Please Note: Since the web sites are not hosted by Microsoft, the links may change without notice. Microsoft does not guarantee the accuracy of this information.
Then please be aware that here we mainly focus on general questions related to Microsoft Exchange server, for your specific query about option within the Gmail app, it's recommended to contact the customer support for Gmail app instead as they would be more familiar with the features of the app. Thanks for your understanding.
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