Why can't I switch my vehichle

Hey, so I tried to join door dash around whenever I was 18. Sadly I was on another persons insurance and not my own and I didn't know that was a problem at the time to i failed to get a job there since it couldn't verify me. Now I have my own car with full coverage in my name. But it absolutely will NOT let me change my car or give new insurance, always tells me i need to submit a form or speak to customer service but I'm always told the same "thank you for submitting, we will get back to you". I tried everything i could to no avail. Any solutions?