Naartjie Downgraded Quality

I bought my son a pair of slides online exactly a month ago and it's already coming loose. I dont understand how these shoes are so expensive but the quality is terrible. I will never buy there again. I'd rather pay this price at woolworths. I have only been buying at naartjie for my son since he was born, it's been 5 years and this is the first time I've received this horrible quality from them! I am guttered honestly. Extremely disappointed!