Hi,
For your HikaShop question, please use the HikaShop section in this forum.
The product custom fields are not editable by the customer, only by the administrator (or vendor in the front-end).
If you want something editable by the customer in the front-end, you should use "item" custom field, not "product".
Because the value entered by the customer for the specific product in the cart will be stored in his cart and in his order.
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.