There are many companies or services that appear to look like they are offering immigration law, but in fact they are not attorneys, they are simply able to assist in completing the required paperwork and provide some advice. Don't be fooled by impressive ads or promises that seem much better than a law firm is offering.
Using a service that is not a true legal firm may result in an incorrect filing, eventually leading to much higher legal costs to avoid deportation or having to re-file and start the immigration processes over. Many of the immigration attorneys have worked within the immigration department or have extensive experience in helping people entering the United States.