Exchange declined

Dear Sir/ Madam, It is with disappointment that I write to you. On the 5the of October 2020 I bought 4shirts on your last sale at your Rosebank Mall Store, all of them were of the same size. I washed them all, I have since used 1, when I tried the next it was ill fitting, then tried the other 2, and they were perfect. My simple understanding of the matter is that the one must have shrunk for it to not fit whilst the rest do. On Thursday the 8th of October 2020 I returned the shirt to the store and I was told they will not accept it. I asked to speak to the manager and was introduced to Minah who vehemently refused to exchange the shirt, sighting that the final return date was the 2days earlier. Now I explained to her that: 1. The final return date was not known to me. 2. Upon purchasing the shirts no one told me of the return date. 3. Your fitting rooms are closed I could not have been able to try these items, meaning I had to take them home to try on. 4. With COVID still on the loose, I had to wash all of them as they did not come in sealed packets. I cannot wear the shirt due to my earlier reasons, I need you to remedy the situation by offering me a refund of some sort, be it cash, a voucher a replacement even if I have to buy the same shirt at the original price, as I had gone to your store not knowing about your sale which simple means I would have paid the original price any way. I cannot accept Minah's explanation that the shirt is now worth nothing to Woolworths, currently it is worth nothing to me also. And I cannot afford to throw away money. Looking forward to your satisfactory response.