Frustrated!!!

Long story ... 15 weeks we were told we are havin a baby boy but she was only 60% sure due to it being so early, 18 weeks we were told they don't know baby wasn't behaving and then today 20 weeks once again they said they were unable to confirm gender and refused to try again so now I am 20 weeks, confused and unsure if my healthy one is a girl or a boy... :( has this happened to anyone else? Can I get another ultrasound covered by my insurance or do I have to pay ? So upset!!