What's up with glass beverage dispensers leaking? Do they all leak or is there something I needed to do to prevent it?

I bought a glass beverage dispenser for a party I had yesterday. I never owned one before, but needed something to serve Sangria out of. It didn’t have lots of instructions, just said don’t carry it while it’s full, and to turn the spigot by hand.

I put Sangria in it, with lots of fruit. It was pouring very slowly, which one person said might have been due to the fruit. It was also leaking, which was very annoying. I tried rotating the spigot right and left, as per the directions (on the directions, it was not clear if it was supposed to be right or left) and the thing just leaked worse, from where the spigot connects to the glass. There’s a rubber gasket in there, and the spigot could be pushed into the glass, but the whole thing was not usable in the way it’s supposed to be used, and we had to scoop the Sangria out and the thing just continued to leak onto the table.

Is there something I need to know about glass beverage dispensers? I am going to return it unless there’s something that I did wrong. There’s still Sangria in it, so I am totally willing to experiment with your answers, a cup and the Sangria!