scrolling problem

While scrolling through the photos in a Gallery, in some cases the scrolling (next – back arrows) does not seem to work as expected. Instead of going through all the photos of the Gallery, at some point one is taken into another Gallery (in our case irrelevent to the first Gallery as they the photos belong to different Projects). Is there a way to manage the scrolling function (and the position of the scrolling arrows on the Screen)?

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