Only Half Of My Adidas Return Refunded Through Afterpay

I had placed an order for a pair of shoes from Adidas and paid for them using Afterpay. However, the shoe turned out to be defective, and I was required to return it. This left me wondering how the refund would be processed. Afterpay initially began refunding me in installments as I selected, but at some point, it stopped doing so. I was expecting four installments, but it didn't arrive until after two. I was perplexed by the fact that I was only given half of what I was owed, so I called Adidas to have the situation clarified. I was given the assurance by the customer service representative that they had refunded the entire amount of $70 to Afterpay. They also suggested that I get in touch with Afterpay for additional assistance. As you can see from what I have written here, still no light.