To disable the tuner you're not connected to.....Menu. Setup. Service searching. Tuner configuration. (Select whichever tuner you're not connected to). Right press select arrow till 'not configured' is selected. Save and back out. Automatic scan.(scan tuner? ,your selected tuner should be selected at the bottom)..OK! ...Autobouquetsmaker…Providers...(select your provider, preferably from the "Sky Uk (SD): area...Ok!...Start Scan.
When this scan finished for me, my 'EPG' populated and all my channels worked......hopefully this is the same problem and this resolution works for you. Let us know eh!