Why do I get an "Ignored ride" notification, if Lyft didn't even send me a request to accept that ride?

That can happen sometimes, and for the following reason:
Skeddy app is checking your "ONLINE/OFFLINE" status with Lyft right before the pickup time.
Most of the time the Lyft server responds with the correct status ("ONLINE"). However, in case, if you did not yet receive a request from Lyft to ACCEPT the ride, the Lyft server can sometimes respond with the incorrect status ("OFFLINE").
In that case, the Skeddy server thinks you're OFFLINE with Lyft and sends you a push notification about a ride you've "Ignored".

Unfortunately, there is nothing we can do about this Lyft glitch.