Hi,
Put a limit ?
Please provide more details about your configuration and your problem.
The option "link product quantity" is here to modify the "product quantity" of the product while associated with a pack.
If the pack have a serial generator, it will set the product quantity to unlimited. If the pack does not have a serial generator, it will set the product quantity to the number of serials in the pack.
If you deactivate the option, HikaSerial won't force the value anymore so you will be able to change the product quantity.
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.