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There are two important differences between light and radio waves:

Difference 1 is the wavelength. Light has a wavelengths of 400-700nm, whereas radio waves used by phones have wavelengths in the mm and cm range.

If structures are of similar size to the wavelength, then waves can "bend around" obstacles. This effect is called diffraction and can be observed with sound waves, electromagnetic waves, water waves, etc.

Difference 2 is the photon energy / frequency. How well radiation is absorbed depends on the photon energy. There are lots of molecules that absorb visible light very well, so it's easy to make surfaces that absorb light. But there are few things that absorb radio waves as well, so it's hard to make things that neither reflect nor transmit radio waves.