Why did Ikea customer service fail to give me a refund?

I cancelled an online order but we just can’t get our money backI am at a loss as to what to do with Ikea and its complete lack of customer service following a failed order and a refund that hasn’t materialised. We placed an order online on 30 December, and a day or two later tried to add on two toilet brushes (a total of £1.80). They didn’t have an option to make the payment online for these extra items, and my husband tried to ring but had difficulties getting through.C