Amazon does not always accept dimensions entered through Stratify or Seller Central in a timely manner.
If you have entered dimensions and they are not being accepted, you are able to submit your dimensions in a different way that is not at the mercy of the Amazon API (the system 3rd parties use to communicate with Amazon).
If you have entered dimensions through Stratify and they are not being accepted after 15 minutes, there are 2 options to quickly get you back on track.
1. Add the MSKU to a shipment plan in Seller Central. This is done by either adding the product to your inventory or locating it and using the send/replenish action.
2. Amazon will prompt for dimensions. Enter the dimensions.
3. Return to Stratify and list the item as normal.
4. After the shipments have been created for the batch in Stratify, it is safe to delete the shipping plan entry in Seller Central. You should not delete the shipment plan or shipment plan entry until the shipments are created.
Add the item to your Amazon inventory in Seller Central and save it.
Once the item is saved, click on Inventory and select Manage Inventory from the dropdown box in Seller Central.
Next, click the Edit button next to the item.
Click the More Details tab and enter the Package Dimensions and Package Weight (dimensions and weight for the item fully packaged).
Note: If you don't see a field for "Package Weight", use the "Weight" field.
Finally, scroll all the way down and click Save and Finish.
Be sure to copy the Seller SKU (MSKU) from Seller Central if you want to use it for your listing in Stratify.
Return to Stratify and attempt to list the item again.
If the dimensions still aren't being accepted, try opening the Seller Central pages in a different browser and try again. If it still isn't accepted, reach out to Amazon Seller Support's FBA team for assistance.