Error when opening the Application (APNX-1-4198-000)

Hello All,

I'm facing this issue while opening the application which contains CDT's, groups and DS.

HTTP Code: 500 APNX-1-4198-000 Error Evaluating UI Expression Expression evaluation error [evaluation ID = a5eb9:bc758] : Appian object error. Details: Failed to execute query in thread for: EngineBackedQueryExecutor [queryKey=DESIGN, typeIds=[23, 80, 200], transformTypeIds=[23, 80, 200], refClasses=[class com.appiancorp.type.refs.ProcessModelRefImpl, class com.appiancorp.type.refs.DatatypeRefImpl, class com.appiancorp.type.refs.ProcessModelFolderRefImpl], reducedExecutor=[ReducedExecutor extended-process-design-service:Process Model,Data Type,Folder (Process Model)]]

Please let me know how to resolve this issue.

Thank You,

Sneha.