The "F/H" fault code will display if water is not detected entering the machine. If water is in the washer before the start of cycle, make sure it can drain it out. If it's not able to drain, disconnect the power cord from the power supply and remove the lower access panel and clean out the drain pump. Note: You will need to remove all the water that you can before removing the drain pump filter cap or all the water will pour out.
Make sure the water entering the washer is not siphoning out the drain hose while it's filling or F/H will display.
If the tub is empty, and water is entering the tub and F/H continues to display, the water level pressure switch is likely at fault and will need to replaced.
Here's my previous answer on this same question: f h error code