Under the Consumer Rights Act 2015, goods should be of satisfactory quality, fit for purpose and as described, while services should be carried out with reasonable care and skill. If goods are faulty, you may have a 30-day short-term right to reject them for a refund; after that, repair or replacement may be appropriate, followed in some circumstances by a price reduction or final rejection. Online purchases usually have a 14-day cancellation period, although exceptions apply. Keep receipts and contact the seller first; Citizens Advice and GOV.UK can explain your situation further.