Because the amount of infringement is not as much as the other party wants, the amount of compensation for infringement of the exclusive right to use a trademark refers to the benefits obtained by the infringer during the infringement period, or the losses suffered by the infringer during the infringement period, including the reasonable expenses paid by the infringer to stop the infringement. You just said that if you only sell a box of infringing products, you won't compensate him as he claimed. The other party claimed the compensation amount of 520,000 yuan, which the court could not support in the case of insufficient evidence.
In addition, if you sell a commodity that you don't know is an infringement of the exclusive right to use a registered trademark, you can prove that the commodity was legally obtained by yourself and explain the supplier, and you will not be liable for compensation.
You should answer the lawsuit, and the result should be no big problem.