Hi,
there must be jquery issue in virtuemart.
are you using virtuemart 3.2 and joomla 3.9 ?
i will fix right now
I am Joomla,PHP programmer having 5 years of experience.
I am very good in wordpress,php,mysql,joomla.
I have done highest projects here in virtuemart..
You can see my joomla profile here [login to view URL]