British Gas owe me money.
Only £42 tbf for an abortive Home Serve agreement where they couldn't cover my boiler
I had an email in February to say the refund would be with me in a 'few' days.
I'm still waiting 
First of all they sent the payment directly to my bank, who then 'lost' it.
They hadn't. I'm with First Direct and I trust them.
They then have allegedly sent me four cheques for £42, all of which haven't (conveniently) arrived. Two different addresses used but still MIA.
How can I convince them that I really do expect them to pay what they owe me??