Medical alert devices that work in apartment buildings?

My sister and I are trying to find something for our mom who lives in a senior apartment in Bellevue. She’s still independent but there’ve been a couple scares, like one time she got up too fast and nearly blacked out. It’s one of those situations where you don’t wanna wait till something bad happens. We’ve been looking into medical alert devices but it seems like some of them have trouble with signal, especially inside buildings. Bay Alarm Medical Alert sounds decent but does anyone here in Bellevue use it? Her place is over near Crossroads and I’m not sure how good the connection is in there. Would love to hear from anyone with local experience.