Aw, that sucks. Yep, I am sure it was a mistake. It is easy to get hoses mixed up. When I worked at a cafe in a department store and at Arby’s in high school, it happened a few times.
Water is alway a safe but or even better if you want soda to buy a sealed bottle from the grocery store or vending machine. At least all those are filled by machine so you know probably no error and you are getting what you brought.