Infinity is very rarely, if at all, ever at the end of a lens' rotation (any lens, any manufacturer, ever) This is due to temperature. If it were at the end for a warm temperature it wouldn't be at the end for a cold one. "Things" expand and contract due to temperature; it's the way of the world. Infinity will be towards the end, turn to the end and bring it back slightly. Many lenses don't even have a hard stop and continue to rotate.
There are many posts/helps on the internet showing how to focus at infinity. A simple technique is to focus on a distant object, it's effectively at infinity.
Thank yourself lucky you're not using film; then it's a real bummer.
I'd advise against SHOUTING in a post; you'll upset some. I DON'T MIND. Also against quoting your serial numbers.