I have same issue since i bought and installed on my domain and installed and test and activated on subdomain now i can’t install same error is coming asking for help to sales as well as themeforest they replied as asked to vender but i have requested twice vender here direct to sales but no one helping .
i am not using theme on any of theme , i have theme earlier never have any issue like this this is the reason bought new x store but it stuck up after 15 days .
is any one will help.