Due to the design with a certain amount of gaps between the mechanism and the seat, there will be a noise produced in an acceptable level. However if the noise is too loud and frequent event for just small movement, more than likely it happens due to lack of oil, or the oil has been dried due to the high level of humidity in your location. Depending on which area is causing the noise, adding some lubrication oil to the area below parts could help fix the issue.
The most common issue is from the connection joint of gas lift and mechanism, which you can add to the area as in the photo below. 
If that isn’t possible or doesn’t work, please contact us at Help Center page and send us a video demonstrating the issue. Our CS team will reach out to you shortly for a solution to resolve the issue.