Minecraft Bedrock button size slider missing

I accidentally deleted and redownloaded minecraft bedrock edition on my iPad Air 2. The data was all deleted so I wanted to redo my control setings to what it originally was. unfortunately, now, I can't find the sliders to resize buttons in the controls touch section of the options. I asked minecraft support on why this is, and they couldn't figure out why. They said to report this as a bug and here I am. Also if this is not a bug but a settings issuse, pls tell me how to fix it as support doesn't know the reason for this.