Hi @radhika_k,
While creating new bundle you might missed specifying Sling Model Package in your newly created bundle(pom.xml).
"To start using Sling Model you need to create a separate bundle for Sling Models, is not required but recommended & specify Sling-Model-Packages, a header in the bundle manifest."
If you navigate to your core bundle's pom.xml, you may see header called "Sling-Model-Packages": Please specify the exact package of your newly created bundle.
eg.
For maven-bundle-plugin
<Sling-Model-Packages>
org.apache.sling.models.it.models,
org.apache.sling.other.models
</Sling-Model-Packages>
For bnd-maven-plugin
Sling-Model-Packages:org.apache.sling.other.models
Hope that helps!
Regards,
Santosh