Shoppers Drug Mart

I bought a gift card for Best Buy on Jun 13, 2019. Two days later, I went to Best Buy and tried to use it to purchase a tv. The gift card didn't work. The cashier told me he couldn't check the balance, and the system said only "Declined".
I went back to Shoppers, and they gave me a number to call. I called the number, and opened a case. I sent the receipt and all pictures they requested.
On July 4 they sent me an email informing me that the issue had been escalated to Black Hawk.
On July 12 they sent another email confirming that the problem was with the manufacturer, and offered me a $100 Shoppers gift card to settle the issue.
I replied on the same day saying this was NOT acceptable. I cannot use a shoppers gift card to make a purchase at best buy. I paid for the gift card with my visa, so I want the money back on my visa. Or they could send me a cheque to my home address.
After this, they stopped replying and I haven't heard back ever since.

I will be making this complaint as short as possible (Many bad experiences) so first off, I worked at this shoppers drug mart and the manager is extremely rude. She would tell everyone I was a great worker but she would say really rude things to my face and in front of customers. She said that I was slow once when I was helping a customer. When she left, the customer was appalled that she even said that to me. She would ask a million things from me and then when I did all that I could, it was never enough. Yet when I worked with her one night, she did absolutely nothing. She was extremely slow, didn't know how to work the cash register, and didn't understand lottery. Shouldn't a manager know those things? I quit after she yelled at me for calling in sick (I only called in sick once in almost a year of working there because I was dizzy and weak and I was shivering non stop) she told me that I should call at least a day in advance to being sick. Not sure how I am supposed to know i'm going to be sick a day in advance. Besides that, she would hire everyone's friends without interviewing them or anything which resulted in a lot of horrible employees. I still go into this store for their sales (I don't have a car and its literally across the street) and I noticed that their refridgerated section always has expired foods. It's disgusting. Also don't bother buying foods that aren't in a well sealed package because they used to have bugs crawling around the back room