They will have to sort it under the sales of goods act or you can refuse the car under the same act as they sold you a faulty product, and within the first 6 months its their responsibility.

They will request the car back to do the work and if you refuse then your loss unfortunately.

Did they supply you with a 3rd party warranty, this may be easier to get done locally.

Or send them a quote for a mobile fitter as i had done, did a cracking job and see if they agree to foot the bill.
http://www.roadchill.co.uk £200 fitted and recharged IIRC.

Also may be in your interest before reporting it to remove the pictures of your bi xenon fitting as they may say you have damaged it yourself if they see the pics.

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