I file my taxes recently and the tax practitioner changed personal information on my return, without my consent. After I sign the original documents.
You likely have tax issues to clear up with the IRS which should be your first step to meet with a new tax practitioner to ferret out the discrepancies between what was filed by the first one and what you had intended to file and resolve them. You could have civil/consumer complaints against the practitioner, and depending on specifics, a criminal complaint as well the bar grievance. While you might not want the answer, your best bet is likely going to be another tax lawyer who understands all of the moving components involved with the forms, documents, processes, and procedures with the IRS - then that person can help point you in the right directions to pursue your civil/consumer/bar grievance options since they can understand precisely what "wrong" the tax practitioner did, based on the specific facts of the incident, rather than just giving general suppositions.
Best of luck