Cough variant asthma

Hi, I am new to the forum. I have a 14 year old daughter who has had asthma for two years. It was diagnosed from her constant coughing. Since February she has had a large amount of asthma attacks. The dr started her on the purple preventor pump and it helped for a little while. In the last two weeks she has had an attack every day. She starts coughing and can't seem to stop and then her chest tightens. A lot of the time the ventolin just does not help. She has started to miss a lot of school as I am having to fetch her every day. We know that aerosols set it off but we don't know what else.
Today I took her back to the dr and asked if it could be cough variant asthma. She looked at me as though I was crazy. How do I convince them that this is what she has. And does anyone have some coping techniques or advice that you could give me to help her please. I am at my wits end and just want to help her get better or cope better. Thank you in advance.