Open the Frigidaire dishwasher's door, completely and carefully. Don't swing the door open to where hot water, dishwasher detergent and rinse aid could come in contact with your skin or spill onto the floor.
Look for objects that might prevent the dishwasher's door from securely closing. Many Frigidaire dishwashers have a rubber gasket around the door frame that forms an airtight seal to keep dishwashing water and food particles in. However, fallen utensils and large food particles could be preventing the door from forming a good seal. Use a paper towel to wipe around this rubber gasket and its contact surface.
Close the door. Press firmly and listen for the latch to engage as a part of the locking mechanism. The Frigidaire dishwasher should automatically resume the current cycle.