Mr Price disappoints

Mr Price recently "ungraded" their mobile shopping app. I have been a loyal customer for years and for the last 2 years have so enjoyed using their original app to shop. Nearly a month ago I bought 3 items off the app. My money was deducted and the app froze but I received an sms saying thank you for my purchase. However, once the app eventually started working again, I found my items still in my "bag" but my money had not been refunded. I have received zero email correspondence to say when and if my items have been shipped or not. I have emailed Mr Price twice over the last 3 weeks to follow-up on this problem and have heard nothing in return. Now the items are disappearing from my "bag" because they have sold out. This app is slow to load and doesn't not work properly. I am too afraid to attempt purchases using it in case the same issue occurs. I am expecting my items to arrive or my money returned. This is bitterly disappointing. I understand glitches occur etc but to not respond to your customer's repeated correspondence is not on. Refund my money or ensure I receive my purchased goods.