The remote server returned an error: (400) Bad Request. when using XMLA + TOM

Hi, 

I'm doing some test to create derivated datasets from a starting dataset, clonning and editing them programatically (https://learn.microsoft.com/en-us/analysis-services/tom/introduction-to-the-tabular-object-model-tom-in-analysis-services-amo?view=asallproducts-allversions) , to maintain them in a future as a synced copy with the original dataset, with some differences in particular (remove some tables, changing the source of other tables). Until now, these are the steps followed:

1.- Create an empty database

2.- Clone the model from the source database

3.- Remove some relationships and tables 

4.- Do a refresh (manually)

An they worked successfully. When I try a similar sequence with a populated model the process fails with this Bad Request (400):

1.- Create an empty database

2.- Clone the model from the source database

3.- Do a refresh (manually)

4.- Remove some relationships and tables  --> Here it fails

The complete message error is: 

ConnectionException: The remote server returned an error: (400) Bad Request. ---> System.Net.WebException: The remote server returned an error: (400) Bad Request.
at System.Net.HttpWebRequest.GetResponse()
at Microsoft.AnalysisServices.HttpRequestResponseExtensions.GetResponseWithErrorHandling(HttpWebRequest httpWebRequest, Boolean isPbiPremium)
at Microsoft.AnalysisServices.HttpStream.WaitForAndUpdateHttpResponseContainingXmlaPayload()
at Microsoft.AnalysisServices.HttpStream.GetResponseStream()
--- End of inner exception stack trace ---
at Microsoft.AnalysisServices.ASAzureUtility.ThrowConnectionException(WebException ex, AsInstanceType asInstanceType)
at Microsoft.AnalysisServices.HttpStream.GetResponseStream()
at Microsoft.AnalysisServices.HttpStream.GetResponseDataType()
at Microsoft.AnalysisServices.CompressedStream.GetResponseDataType()
at Microsoft.AnalysisServices.XmlaClient.EndRequest(Boolean useBinaryXml)
at Microsoft.AnalysisServices.Core.Server.EndXmlaRequest()
at Microsoft.AnalysisServices.Core.Server.EndXmlaRequestWithReader(XmlaResultCollection& results)
at Microsoft.AnalysisServices.Core.Server.ExecuteReader(String command, XmlaResultCollection& results, IDictionary properties, Boolean wrapCommand)
at Microsoft.AnalysisServices.Tabular.ExecuteUtil.RunCommand(String commandText, Boolean requestImpact, Int64 impactSinceVersion, Server server, ImpactDataSet& impactDataSet)
at Microsoft.AnalysisServices.Tabular.ExecuteUtil.TryExecuteXmla(Model model, String xmlaRequest, XmlaResultCollection& xmlaResults)
at Microsoft.AnalysisServices.Tabular.Model.SaveChangesImpl(SaveOptions options)

and it occurs after several minutes of doing something (processing?)

Any Ideas?

Regards

Alexis