Which one (and from where)?
30 'Gold' stations were re-branded as 'Smooth Radio' back in 2014.
The remaining four stations should still be available on Medium Wave (London 1548kHz, Manchester 1458, Nottingham 999, Derby 945) as well as via DAB radio in some areas.
Satellite TV viewers can receive the station too (Sky 0121, Freesat 722) as well as subscribers to Virgin Media (Ch 923).
There are dedicated apps for Android devices, as well as for iPads and iPhones.
You can also listen online by clicking here:
http://www.mygoldmusic.co.uk/radio/player/
So where have you lost the station from?