I’ve often thought this was a quick work-around but wonder if it works because not enough people use it? For example, what happens if the robocaller sends 0-9

I’ve often thought this was a quick work-around but wonder if it works because not enough people use it? For example, what happens if the robocaller sends 0-9 digit tones in rapid succession? Does it let them through even though they got it wrong an average of five times before getting it right? They could even use voice to text to listen to the number requested. I would love if my provider had this feature but it doesn’t. So I end up whitelisting my contacts and putting my iPhone into Focus mode. One of the ways of getting past Focus mode default settings is to call twice in fast succession. I’ve noticed some robocallers calling, hanging up immediately and calling right back which puts the call through.