Sky 1, 2 & X 'service unknown'

I've had a problem with all the S*y sports channels since early this morning - tried manual scan on frequency 491 (S*Y Sports 1). But no success. Has anybody else had this problem and how did they sort.

Ps have Eurovox 2008

 

Delete the channels manually and do an auto scan and the new channels will appear at the end of your channel listing

 

Thanks Celtic71 - Did as you suggested & worked a treat. New to all this so was apprehensive - thought might lose other channels by auto scanning (is this a possibility?).