To everyone that has experience spam TEXT messages (not phone calls), I got this from Verizon support this morning:

You may report the spam message by following the steps below:

1. Please forward the suspected SPAM message to 7726.

Note: There is no charge for this text message.

Result: You will receive a free text message requesting the identity of the "From" address on the suspected SPAM message.

2. Please reply with the "From" address.

Note: This message is also free.

Result: You will receive a free text, "Thank you".

3. The investigation will begin the same day the messages are sent to the short code, but you will not receive any further updates.