4K and 60FPS on LG external monitor

Hello all,

I am using the MACBOOK Pro 13" 2016 model (with sierra 10.13.2 version) with an original type c adapter for hdmi output. Recently i bought an LG 27UD68P 4K monitor as external. I checked that type c adapter along with the LG monitor supports HDMI 2.0 which means that normally i should be able to select 4K @60Hz output.

However, the only options are 4k @30HZ and 1080p @60Hz and my mac recognize the monitor as 30inches and 1080p.

Does anyone know if my cable is the problem or this is the max resolution via a type c adapter?

Thank you all,

Dimitris