There is a product defect in the Sitecore.Commerce.DynamicsIntegration.Routing.8.1.399.0 update that prevents it from synchronizing more than 1000 products data from Dynamics.
To resolve the issue, consider one of the following options:
Option 1: There is no existing deployment of Sitecore.Commerce.DynamicsIntegration.Routing.8.1.399.0.update.
Use Sitecore.Commerce.DynamicsIntegration.Routing.8.1.401.0.update for your new deployment. The other Dynamics related packages have not been changed and you can get them from Sitecore Developer portal page.
Option 2: The Sitecore.Commerce.DynamicsIntegration.Routing.8.1.399.0.update has already been applied.
Use Sitecore.Commerce.Endpoint.DynamicsCrt.dll file to replace the same file in the \bin folder of your existing solution.
Option 3: The Sitecore Commerce DynamicsIntegration Routing is customized based on the DynamicsRetail.Routing.8.1.399.0.zip.
Download the DynamicsRetail.Routing.8.1.401.0.zip and merge the changes into your customized code. The files changed by this hotfix are:
Note: If you are using the routing console application, you must update the dependent Sitecore.Commerce.Endpoint.DynamicsCrt.dll with the version from this article.