Am stations but no fm stations

AM reception is much less sensitive to the connections of the antenna than FM stations are. For example, you might be able to receive AM stations with just the ground wire of the antenna connected to the radio and not the center wire (which connects to the antenna’s main mast). And some radios also use the main chassis ground as an additional reception point for AM so you might be able to get AM stations with no external antenna connected at all. First step is to check the integrity of the center antenna wire that connects to the antenna’s mast. There should be clean, low resistance connection between the antenna wire’s center connector at the radio and the main mast of the antenna. If you can, try connecting a different antenna to the radio and see if FM reception improves. That will tell you if there a break in the wires or some other fault with the original antenna.