New replacement battery holds charge for 2 hours.

Where did you get the new battery from? If you purchased a cheap battery online then it’s very possible that’s exactly what you got, a cheap battery. While with some things, batteries are not one of those things you can cheap out on. You get what you pay for. Now if you did purchase the battery from a reputable source then it’s likely you just got a bad battery. This happens from time to time. The battery should have a warranty so I would take advantage of that. If you are looking to purchase from somewhere else or even in the future, be wherry of any place that does not offer a warranty.