auto-resize Guest Screen Display in Virtualbox

I have just installed Ubuntu VM on Virtualbox from Manjaro OS host machine.

It has properly installed BUT the auto-resize to full screen does not appear to be working properly.

Forgive me I am a noob as far as Linux and virtual machines go.

Attached Images

• Screenshot from 2024-08-24 16-59-36.jpg (16.9 KB)