We are aware in some incidences where guests are using GMAIL that reservation emails may show with a unique 'header' created by Google Trips but where they (Google) populate the wrong hotel listing or even address details.. The Inn Style reservation that follows this 'header' is however showing correctly.. example below:

If a customer calls you to say their confirmation email is incorrect, they can be advised to 'turn off SMART FEATURES in their GMAIL settings' as highlighted below, and this should stop their reservation emails showing incorrectly with just the Inn Style reservation details showing instead as per their booking.