If you have tried everything and the person is still going straight to voicemail or a busy signal, it is possible they are not blocked—there might be a different issue:
Follow the voice prompts. Usually, you will need to press the key to unblock a number. Enter the 10-digit phone number you want to unblock. Press the pound (#) key to confirm the removal. how to unblock a number from a landline
Here are the three most common methods to unblock a number. If you have tried everything and the person