Treating customers fairly - bad mouthing clients

I went to Toys r us Clearwater mall to buy my son a Christmas present in December 2020. We bought a Paloroid watch for him, he opened it on Christmas and it was not working, we took it back on 27 December 2020 to go an exchange it, but as expected they did not have stock, which is understandable, we were told they will get in middle January, we waited till then, and I called again and spoke to Pearl, the manager there, which was friendly at the time, but well, that was just a face. When I called they said they have not received stock yet and will call me, I had to call once a week, because there was such a lack of customer service, just to be told the same thing, they don’t know when they will get in stock, each time, I asked why can they not phone to find out! needless to say, by last week, I have had it, but still called in and left a message for Pearl to call me back, she did not realise she dialled my number, and I had to sit and listen to her, how she is bad mouthing me! How "naar" I am busy making her! She dropped the call and called again, but I then told her that I heard her talking about me like this, and I am going to lodge a complaint against her. We told them that they need to get this sorted, my husband went there today because according to them they received a brand new watch, he got there, the box was opened, no sticker on the watch, and not even a charger in the box! Now we are back to square 1. I am so sick and tired of no customer service, and still to treat clients like this, how is this treating customers fairly?