Feed rejected Error Code: InvalidMarketplace. Error Type: Sender
The error you receive: Feed rejected Error Code: InvalidMarketplace. Error Type: Sender
Description: In most cases, this error is connected to the status of your seller account on the amazon marketplace. Please navigate to a seller central on your amazon marketplace. Please check your seller status (Settings > Account Info).
It should be "Active".
Example on the picture:
In certain cases, you can get here an active and valid status but still can't export products.
Then please try to add products via the amazon interface:
1) Catalog > Add Products
2) Select "I'm adding a product not sold on Amazon"
3) Choose one of the amazon category using the category tree
In a normal situation, you should get a new page where you can enter your product details.
If your account has some errors with the configuration you may see the following page:
Please try to "Reactivate Account" and if this didn't help contact amazon seller support.