Without worry about the father coming 1 to 2 year later and try an change the child's name. Please help us single mothers.

I am a single mother of a amazing little girl. Her father was never involved in her life. He was not there during the pregnancy an was not there for her birth. He knew that I was pregnant before he left. I tried to contact him while I was pregnant and if I saw him in a store he would leave what he was buying and leave. I tried to tell him. I even called his moms and my uncles told him. He knew about her, but he choose not to call.He abandon her, an she is now 2 years old and he has took me to court to have her last named changed to his. Please help me change this law.