how can i fix my gainsborough 10.5scl?

my shower water output is down to a trickle and cold when i turn the temp control nothing alters HELP
DEREK HOLT, March 2007
tried without handset still the same

derek holt, April 2007
have you tryed cleaning the shower haed

hi-spec plumbing, March 2007
link Click here to see other fixes for Gainsborough.