YOU SAID:

I would only like to negotiate a fish paste discount

INTO JAPANESE

私は魚のペーストの割引を交渉したいと思うだけです

BACK INTO ENGLISH

I just want to negotiate a fish paste discount

INTO JAPANESE

私はちょうど魚のペーストの割引を交渉したい

BACK INTO ENGLISH

I just want to negotiate a fish paste discount