If your agreement is with the cleaning company rather than the individual cleaner, then they are liable in principle; if your agreement is with the individual cleaner they may still be liable, it's just a bit more complicated. Get a quote for repair/replacement or whatever is need to put it back into it's original condition, send a copy to the firm and ask them to pay/agree to pay within 7 days, or you'll make a claim. Making a claim is fairly straightforward - there's lots of guidance online and in my experience most court offices are pretty helpful.

http://hmctsformfinder.justice.gov.u.../ex302-eng.pdf

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