Can't scroll plants selection  bar in levels .

I am having the same issue.  I recently bought a Samsung Galaxy Tab S10 Ultra.  Are you maybe playing on one of the Ultra tablets?  I think it may be related to the Ultra's wide screen.  I tried all the suggestions I found, like setting the screen to not full..  But nothing seems to fix it.   It's a pain to do this, but a work around is make the plants you want to select for Arena or Adventure  favorites so they appear at the top of the plant selection.    So you can select them without  having to scroll down.  I found comments made for this same issue from 4 years ago on this forum.  Following is a link.  The last comment on this link is mine.

https://forums.ea.com/discussions/plants-vs-zombies-2-en/re-the-plant-picking-part-from-a-level-is-lower-on-the-screen-and-i-can%E2%80%99t-scroll/10264655