ITEMS NEVER DELIVERED - NOT GETTING A REFUND

I placed an order for 3 items on 16 Jan 2023. After contacting them numerous times they delivered a short order on 15 Feb 2023 (which was supposed to be delivered in 18 Jan 2023 according their website). The delivery guy advised that the outstanding item will be delivered as soon as they have it in stock. I've tried to contact them several times since then to request a refund and still haven't received any feedback. We phoned them this week and the lady advised that the warehouse's website shows that the item hasn't been dispatched yet. We asked for a refund and she confirmed that they will refund the money into card used for the online purchase. IT'S BEEN ALMOST 7 WEEKS SINCE I PLACED THIS ORDER, I JUST WANT A REFUND FOR THE UNDELIVERED ITEM!!!