100000 miles. And repair cost can be £1000+

I purchased my car April 2021. The wet belt has failed with only 54000 on the clock. This should not have happened with such low mileage. I've contacted trade centre Wales and they have denied responsibility and said try Citroen itself. Citroen MAY do a good will repair but no guarantee. I still have 2 years finance left to pay and no car!! The car was sold to me with no book or service history, no option for extended warranty or gap insurance. Where do I stand?