Can’t get hard when with a girl

The last 2 times i tried to have sex with a girl I was just staying soft ,because of how nervous I was and that was it. Then I had this girl at a party in her house , we turned off the lights and we were like hugging and stuff and I eventually got hard , but I was too afraid to actually do it. The thoughts of getting soft were terrifying me.
So there you go 3 attempts with zero success rate… A bit desperate at this point.