check the screen where the hose hooks to the washer. it may be plugged.
You may want to check that your cold water knob is all the way open. past that check for a blockage in the hose.
Good luck!
It might be clogged with deposits. Take it off and check.
Check to see if the screens inside the water-inlet valve are clean. (The water-inlet valve is the device on the washing machine that the fill hoses are attached to.) If they’re clean, you probably have a defective water-inlet valve. If so, you should completely replace the valve.