With us it is *57.
That only works if you report immediately after the receipt of the call. If another call comes in, the report is lost.
The telephone company discourages use of that feature. I think the fee for each use is now $5.00. They have stated as policy they only respond after a minimum of five instances, and they must be serious problems, such as profanity, harassment, threats, etc. I don't [think] they would respond for inappropriate sales calls, especially for only one occurence.
As to having a lawyer be involved, that represents a considerable cost, not worth the [money].