Hi,
The 2Checkout plugin has been made by MintJoomla
It is not a plugin we made so, we might take a look at the plugin in order to see if there is a problem but just to warn you, we can't make you any promise. The best is to contact MintJoomla for problems related to their plugin.
But, like I said, you can send the plugin to nicolas (@hikashop.com) and he will take a look.
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.