There is a place to collect water called traps in the drainage area around the water, and it has a function to prevent invasion of odors and pests from the sewer pipe.
If the water is not used for a long time due to the absence of long-term use, the water in the drain trap evaporates and the odor rises. Please operate the washing machine(supply water ~ dehydration) to fill the water in the basket.
Also, if the drain trap (where water accumulates) is loose, odors will come out from the gap. Tighten it clockwise and check for looseness.
* If the washing machine is not equipped, draw water into the cup and pour it into the drain.
If there is no improvement after trying the above, please let us know via the "Contact Us" or our sercive center.