Massachusetts insurance regulators Friday rejected a proposed 7.2 percent rate hike by the FAIR Plan, the state’s home insurer of last resort. The FAIR Plan had proposed raising home and condo insurance rates by 6.7 percent on the Cape and the Islands and 9.9 percent in several other areas, including New Bedford, Worcester, and Springfield. The plan, currently covers 201,150 householders who are unable to obtain coverage from other insurers, often because they are thought to be at high risk for flooding, hurricanes, or other disasters.