Hi @Gowthamprabhu Sivaraj ,
Thank you for reaching out to community
for the UI you should use the validation service(validate hook) instead of the beforesave since currently it is not possible
Please use the Validate hook you will be able to see the validation clearly in the UI
Also try using the DVF error action from the data modeler for the entity types
here I have defined firstname as mandatory and record will not be saved when the firstname is populated
be sure that you need to enable the validate hook with dvf lca into data model for entity type for this functionality work
"lifecycleActions": {
"validate": [
"Reltio/DVFAction"
],
"beforeSave": [
"Reltio/DVFAction"
]
}

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Shivaputrappa Patil
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