I have a question about the loading position of the prototype changes

I was running a user testing session and asking user to load my figma prototype on participant’s phone. With the participant opening the prototype on different phone sizes, I have noticed on several occasions when a user open the link, there is a screen where the user lands on sometimes would hide the area of my figma prototype on the top. as if the page has been scrolled to a certain point on the page. (it’s a long scrollable page)

Is that something that I can resolve? or is that because users are using different devices.