strange keyboard behaviour - typing snaps to top of screen

[neuronetv]

galaxy s23 ultra
One UI 7.0
android 15

in a couple of apps (whatsapp and myphoneexplorer) I have this really annoying keyboard behaviour problem. when I'm typing, the text snaps to the top of the screen. its driving me mad. I dont think its the apps, its a problem with the phone or the phone keyboard.

I've made a couple of screen recordings that show the problem:
https://drive.google.com/file/d/1WUF1vaN0aFLcP9J98_ZWlBx9seYFW2zM/view?usp=sharing
https://drive.google.com/file/d/1hHXL7YNbKst_HcozAj_61PVkG_MiGKtE/view?usp=sharing
hope you can view the videos.

thanks for any help in solving this.