You may want to test the kitchen water lines before the faucet. 2 people can do this by removing RV water pressure, disconnecting the lines one at a time from the faucet, covering the open end of the water line before the faucet with a large towel or aim it at a collection basin, have a helper turn on the water pressure momentarily and check for water flow. If you have water flow through the tubing with this test, I would diagnose your faucet as being clogged/defective, and replace it. If there is no water flow through the tubing, you need to back blow out your water lines with compressed air by removing the water line connection at the city water inlet fitting, covering that with a large towel as best as you can, and shooting short shots of compressed air from the faucet end to the inlet fitting end, seeing if there is little backpressure during the compressed air shot, and inspecting the inlet tubing water collection towel for foreign matter debris blown out from the tubing.