src/Tree/Controllers/TreeController.cs

@@ -404,7 +404,14 @@ namespace Coscine.Api.Tree.Controllers
             }
             else
             {
-                _rdfStoreConnector.CreateNamedGraph(graphNameUri);
+                try
+                {
+                    _rdfStoreConnector.CreateNamedGraph(graphNameUri);
+                } 
+                catch (Exception)
+                {
+                    // Graph creation failed because it has been created before, skip this for now
+                }
 
                 if (CoscineLoggerConfiguration.IsLogLevelActivated(LogType.Analytics))
                 {

src/Tree/Tree.csproj

@@ -5,7 +5,7 @@
 		<AssemblyName>Coscine.Api.Tree</AssemblyName>
 		<GenerateDocumentationFile>true</GenerateDocumentationFile>
 		<TargetFramework>net6.0</TargetFramework>
-		<Version>2.6.3</Version>
+		<Version>2.6.4</Version>
 	</PropertyGroup>
 	<PropertyGroup>
 		<Authors>RWTH Aachen University</Authors>