Very poor customer service

I ordered 2 pairs of Skechers light-up sneakers for my children on the 12th of December 2017. On the 20th they cancelled the pair for my daughter (which she was very excited about) then only send the pair for my son which I received on the 22nd (10 days after I placed the order) On the 10th of January I wanted to put the shoes on for my son but noticed immediately that one shoe doesn`t light up at all. I then immediately send a request to onedayonly to please come and collect the shoes and exchange them or refund me so I can buy a new pair. I received a mail from onedayonly on the 11th that they contacted the supplier of the shoes and will collect the shoes and refund or exchange them. It is now the end of the 16th and I haven`t heard anything yet and the shoes are still not collected. Why are your return customer service so poor? Shouldn`t the package be picked up within 48 hours after the return request has been logged so you can assess the shoes then exchange or refund the client? Tomorrow a week will have passed and I haven`t even got a reply from onedayonly to date. Can anyone at onedayonly get back to me with any kind of reply as to if I will receive an exchange or a refund and when this will happen? Regards Leoni Pretorius