Does T-Mobile "Scam Shield" app not block scam from verified numbers?

Scam Shield app on my iPhone seems to have worked okay until recently.  But that changed.  The app now says, "Scam Block is on. 7 scam likely calls blocked in the last 30 days."  But I've personally reported 58 calls from a dozen or so boiler rooms in the last four days.  Many of those are from the same numbers received after I reported them as spam.  The calls are robo-dialed.  Often they hang up when I answer.  Other times a person comes on the line.  The callers are looking for Clara Kendrick who lives in West Virginia.  That's not me, and I don't live there.  The callers are looking for health insurance sales leads.  I checked with Healthcare.gov and was told there were no applications there from anyone using my phone number.  Some of the nuisance calls have come through more than five times.  There so many I cannot be sure, but I think the calls that come through repeatedly are from verified numbers.   I've started using my iPhone feature to block those numbers.  But I'm still curious.  I talked to T-Mobile tech support but couldn't get any answers that made sense.  Can someone explain what it is about these calls that evades the Scam Shield app?