Bad service

I have done a refund and 5 % of the money is missing and I once did a refund and I received the whole funds,they policy say you have 7 days to return cooling off period I returned the couches in 2 days and I waited for my refund for more than 21days and it was not captured since lockdown .i want my full refund to be payed in my account As I payed them in full Aswell they must explain to me why I got the whole refund at first and with this one I’m not getting the whole amount I didn’t buy online they must practice they policy .they thought I’m gonna leave it they must refer back to their policy I bought in store and I want my money back