My developers made some customization for workpress site and at the end here is what they said:
"Changes which was required for your theme improvements are not going to added in ThemeForest directory theme, so yes if you update theme with updated theme , you will loss your customization work. Child theme is not used as we improved/ changed code "
It means I can not update my theme nor will loss the custom work.
With this dispute, who should i contact as a 3rd party to solve this dispute?