Hello,
Would it be possible to have some details about what you have done and a link to your website product listing with the filter configured ?
Some information regarding the filter configuration would also be required to perform tests or understand the global behavior.
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.