Hello,
Kindly note that in the Product Grid/Carousel element, the “Items per page” option is a global setting and is not device-specific. This means the value you set there will apply to all devices (desktop, tablet, and mobile), which is why it reverts to a single value after saving.
For responsive control (different columns per device), you should use the “Columns” settings, where you can define separate values for desktop, tablet, and mobile. The “Items per page” field only controls the total number of products displayed, not the layout per device.
Please adjust the columns accordingly, and your layout should work as expected.
Best Regards