Okay, you might have a confluence of conditions here. First, those battery health apps measure voltage change as an indicator of ability to hold a charge. The problem with that is they either use a generic baseline, or they use the battery's current charge state as the baseline. What it may be telling you is that it's okay for a 2-year-old battery. This doesn't mean the battery isn't losing it's ability to hold a charge. I would expect a 2-year-old battery to be showing it's age. Add to that a high drain /always-on app like alexa and you could easily see losses of 10%/hour.