‘Your problem is the delay, as your rights diminish with time’
Given the time that passed between the purchase and complaint, your options are limited. Under the Consumer Rights Act, all products must be of satisfactory quality, fit for purpose and as described. The problem you have is the delay in bringing this to the seller’s attention, as your rights diminish with time. In the first 30 days you can demand a refund. Between 30 days and six months you have the right to have the goods repaired or replaced. After six months things are complicated as it becomes the buyer’s responsibility to show that the goods were faulty when bought.
The key to dealing with faulty goods is to act fast. Check any items you buy, in their intended environment, as soon as you buy them. If there is an issue, put complain in writing. Explain what the issue is, the outcome you want, quote the law (Consumer Rights Act 2015) and threaten legal action if required. This tends to resolve the complaint at the first time of asking.