Worst service received ever.

Went to McDonald's in promenade Mitchell's plain was served by crew id 45 Lorna L. She took our orders and went to pour the drink left my drink open the whole time. She then decided to take other orders and when my order finally came she went to take the unattended drink to provide me that was left opened for good 5mins. When I asked about it she had the decency to tell me she had just poured the drink, when I was literally standing right in front of her and decided to give me an attitude. I don't know if maybe that's what McDonald's training contains bad customer service and to mistreat customers. The whole of McDonald's has lost a customer