Your Samsung Tab S6 Lite keyboard likely shrunk due to a setting change, which you can fix by going to Settings > General management > Samsung Keyboard settings > Size and transparency, then dragging the handles to resize it. Alternatively, open the keyboard, tap the three dots (toolbar) or gear icon (settings), find "Resize" or "Size and transparency," and adjust it, or reset settings if needed.
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How to Resize or Reset
1. Resize Keyboard (Direct Method)
Open any app that brings up the keyboard.
Tap the three dots (⋮) or gear icon (

) on the keyboard's toolbar.
Select "Resize", "Size and transparency", or "Keyboard size".
Drag the blue handles (arrows) on the keyboard's edges to make it bigger or smaller.
Tap "Done" to save.
2. Through Settings (If toolbar option missing)
Open your tablet's Settings app.
Tap General management.
Tap Samsung Keyboard settings.
Select Size and transparency.
Adjust the size using the handles and tap Done.
3. Reset Keyboard Settings (If resizing doesn't work)
In Settings > General management > Samsung Keyboard settings, look for an option like "Reset to default settings" or "Reset keyboard settings" to return everything to normal.