2007 Vauxhall Meriva pulling to the left

If you have had the alignment done 3 times ,it was either done wrong in the first place or there is something worn on steering / suspension which is causing it to upset and vary steering geometry .If there is wear on steering and /or suspension , your are wasting time and money getting alignment done till it is fixed and wear eliminated . You haven't kerbed it or went into any large pot holes causing something on front to be bent ? Surprised any one would adjust wheel alignment 3 times without checking reason for it being out again .Why don't you try somewhere else and see what their findings are .