by testimony from Alan W. Pullen, president of Community. 5 . Hudson v. Inman, 179 S.C. 399, 184 S.E. 102 (1936). 6 . Community argues again on appeal that this issue is moot. A case becomes moot when judgment, if rendered, will have no practical legal effect upon the existing controversy. Mathis v. South Carolina State Highway Dep't, 260 S.C. 344, 195 S.E.2d 713 (1973), cited in Arnold v. Association of Citadel Men, 337 S.C. 265, 523 S.E.2d 757 (1999). This is true when some event occurs making it impossible for the reviewing court to grant effectual relief. Id. However, a foreclosure sale that was improperly conducted so as to prejudice interested parties is void and, therefore, the sale may be set aside by the reviewing court. Howell v. Gibson, 208 S.C. 19, 37 S.E.2d 271 (1946) (<HOLDING>) (citation omitted); Farr v. Sims, 9 S.C. Eq.
holding a mistake or surprise in connection with the sale is grounds for setting it aside provided the mistake is harmful and not a mistake of law or one due to the negligence of the party complaining holding breach of best execution duty is a material misrepresentation in connection with the purchase or sale of the securities holding that it is unlawful for a person to omit material facts in connection with the offer or sale of a security holding that common law grounds such as manifest disregard of law and gross mistake were not valid grounds for vacatur of arbitration award as hall street forecloses any common law grounds for vacatur holding that the role of the courts is limited to ascertaining whether there exists one of the specific grounds for the vacation of an award as provided in  10 of the arbitration act and that the court should not review the arbitration proceeding for errors of law or fact