Studio 88 Online Refund ( Bad service)

Last year November I bought 4 items from studio 88 online. I returned 1 t-shirt because it was a big size and requested that they should send me the correct size. The courier collected the t-shirt from me. After a week or so I sent an email asking when am I going to get the correct size of a t-shirt as I requested, I was dealing with a guy called Caitlind Stuart. Caitlind told me that they haven't received the parcel that the courier collected from me he will give an update as soon as they receive it. after a week I sent Caitlind an email again asking if they have received the parcel he said they still haven't received it, that was in the beginning December after a few weeks I sent an email to Caitlind again asking when am I going to get my parcel then he said finally they have received it he will notify their warehouse to send the tshirt with the correct size that was in mid December. I waited waited and waited for my parcel to be delivered unfortunately it was not delivered. towards the end of December I decided to buy same tshirt at studio 88 with the size that I wanted which is 9-10 because it was for my son. I sent Caitlind an email and told him that I want a refund of the tshirt that I returned he said they will start processing my refund. Beginning of January I sent emails to Caitlind regarding my refund Caitlind was not responding to my emails. I Called the head office and was transferred to Shane because he deals with online issues. I told Shane the whole story Shane said he will address this and have it resolved soon. Shane sent emails to their finance department and to Caitlind as well and told them to process my refund. On Monday the 13th January Caitlind sent me an email requesting my banking details and confirmation letter from the bank on the same day I sent him everything that he requested from me. On Wednesday I sent him an email to confirm if he received what he asked for, Caitlind did not respond on Thursday I sent another email to him to please confirm if he received the banking details and confirmation letter again Caitlind did not respond. it is now Friday I haven't gotten anyfeed back. I have been fighting with these people for 2 months over a refund of R319.99 I'm tired honestly. If I could just get my money from studio 88.