I bought the laptop on line , firstly it took forever to be delivered, eventually I received it

I bought the laptop on line , firstly it took forever to be delivered, eventually I received it .upon arrival I realised the screen was very small compared to what I expected, then when I realized that’s it won’t work with the applications I want run I opted to exchanging it . Now I’m struggling to do an exchange or a return . I’ve been trying to call no answer, request a call back nothing , chat to a consultant only to be given so many links which get me nowhere , then finally got an email adress I can use but still is been a week now without any response .