I know this has been answered already but the answer even by VZ staff seems to vary and be inacurate. I recently tested the VZ call and text block that you update through your account online and it did not work as directed. I blocked my friend who has a VZ iPhone. She messaged my android (galaxy s4) and received no error or undeliverable message to her phone. When she called she did get the automated message that says "caller has restritictions" etc. The VZ support said that the person blocked will get error message back but then why didn't she? Also it was not sent as an imessage by accident as it was a green message box.
I apologize that you're having the issue with the call and text block feature. When you applied the block to that person's number, do you know it call forwarding activated on that person's line? Double check the number along with no call forwarding.
Thank you! EdW_VZW
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