phone won't ring calls go straight to voice mail

So apparently, there is a feature in:

Settings > phone > silence unknown callers ... this even apparently is STRONGER than Do Not Disturb because even if the call was within 3 mins of each other, it still went to voicemail! Hope this helps and T-Mobile, you are welcome for solving this issue for some hopefully! And yes, T-Mobile can contract me for an IT Project Management role is needed. ¡Gracias!