My (older) phone is running Android 7.1.1. (In case it matters, the phone is a ZTE Axon 7.) I use the phone app that it came bundled with, "Dialer" v 4.2.001. (That's a really generic name, I know. I'm not sure how to get more identifying information.)
As usual, the phone icon shows a red alert with a number for missed calls. This has worked fine for years. About a month ago, after a missed call, I opened the app to see the caller info, as usual, but the notification did not clear. I've had an incorrect "1" stuck to my icon ever since.
Yesterday it happened again. Now I have an incorrect "2" stuck to my phone icon. I found the app settings and tried turning notifications off and back on -- didn't help. Just turning them off and *not* turning them back on didn't help. (That would be inconvenient long-term, but in the interests of debugging...) Restarting the phone didn't help. Clearing the app's data didn't help.
Both of the triggering missed calls were suspected spam according to Hiya, but I get *lots* of calls from "Spam Likely", never answer them, and most of the time don't see sticky notifications from them. I don't know what else the two calls that triggered this change in behavior have in common.
Web searches have led me to lots of other people who have this problem, but have not led me to a solution. How can I clear this *without* uninstalling and reinstalling the app? Since it came preconfigured I don't know what I would have to do to make a fresh installation work (assuming I can find the same app), and I do actually care about getting (some) phone calls.