For most channels, when using Lengow, the information entered on the marketplace's back office will be replaced whenever a new feed is exported from Lengow.
This is true even if the information remains empty on Lengow. In this case, the data will be replaced with an empty value on the marketplace.
It happens because the configuration on Lengow has the priority over the data set up on the marketplace's side.
Nevertheless, it is possible to avoid having your data erased when using Lengow for Amazon.
On Amazon: Set up the attribute "operation-type" to "PartialUpdate"
When "operation-type" is set up to "PartialUpdate" on Lengow, it means that the information entered on Amazon's side will not be replaced once the feed is exported from Lengow, even if the information is set up on Lengow as well.
Please note that this method only works with Amazon.