Hi,
For question related to HikaMarket, please use the HikaMarket section for the forum.
Your product "basic product" has been configured to use the plugin "vendor group after purchase".
That plugin is there to change the vendor user group after the product is bought ; so it means that only vendor have the right to buy his product.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.