told I was stupid and could not read

I bought clothing about 3 weeks ago. The Assistant had clothing boxes everywhere including change rooms. So I did not fit the clothing. When I got home I realized she had given me S instead of XL which is obvious that I am. I called the shop. They agreed to exchange the clothes. They located the correct size after 3 weeks. I went to exchange yesterday. The shop was closed. Had a sign back in 10 mins. Because it was late I looked for a number to call on the shop window. They had jobs advertised with 2 numbers displayed. I called the mobile. A lady answered I asked if the shop was still open