FBA error when it is an FBM item


We are getting this error when trying to update inventory: An FBA offer already exists on this SKU. To create a seller fulfilled SKU, either create a new SKU or make the SwitchFulfillmentTo value MFN.
The items are FBM?


The error is saying that the item is FBA but you area trying to make a FBM offer.


No the item is FBM, but it is saying it is FBA.


You may need to double check that.


To expound on @Buildcom’s comments with some questions.

  • Do you actually already have the SKU in your inventory?
  • Do you have your account set to FBA for new listings?
  • Are you using the API’s or doing this through Seller Central (This forum is for the API’s)


Yes sku is already inventory, no it is set for FBM. I am using 3rd party API. The ywere able to update inventory jsut fine until I starting sending in a FBA shipment which is for a separate SKU.


Other Sellers report the same issue:


Thank you for sharing. I have reported this to MWS support. Please have those sellers submit tickets as well.


UDPATE: I was able to fix this by
Get out of this program, and everything will be back to normal.

Inventory > Remote Fulfillment with FBA > Unsubscribe

UPDATES via API will return to normal. @MythicalSet

Thank you.

Still don’t understand, because I was already in this program then this error appeared once I started sending in a fba shipment which is for a totally separate sku.


We don’t want to unsubscribe to Remote Fulfillment with FBA. The other solutions seems to be to update your inventory feeds to also include the “SwitchFulfillmentTo” field with the value “MFN”


I ran into the same issue. It worked fine for several months, until a few weeks back.

What program is everyone using? I have Brightpearl - handles inventory sync and orders. I am curious if this is one program or multiple different programs.

@nwecom @SUNDANCE @Candid_Company @MythicalSet


it happens on multiple programs