Such issue is related to server settings as a rule when you have limited writing permission and theme can’t install plugins automatically. It’s not related to theme but to your server. Anyway, we need to check the issue and confirm that problem appears and it’s related to our theme, only after that, we are able to give refund https://themeforest.net/page/customer_refund_policy
We can’t give you refund without screenshots of the error from your side and without checking the error, sorry.
