Hi,
Please go in the HikaShop configuration panel and click on the "check database" button.
It is possible that your database is not fully up-to-date which could explain the saving issue.
If it does not fix the issue ; it could be interesting to display the PHP error message and to activate temporally the Joomla debug mode (these two options are in the Joomla global configuration).
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.