@sandeep_k_singh
If you already tried @keerthi0555 solution, try the below to debug the issue:
1. Check that the component policy is correctly configured in the _cq_design_dialog folder of your component. The _cq_design_dialog/.content.xml file should include the <styletab> entry to enable the Style System tab, as shown in the example below:
xml
<tabs jcr:primaryType="nt:unstructured" sling:resourceType="granite/ui/components/coral/foundation/tabs" maximized="{Boolean}true">
<items jcr:primaryType="nt:unstructured">
<styletab jcr:primaryType="nt:unstructured" sling:resourceType="granite/ui/components/coral/foundation/include" path="/mnt/overlay/cq/gui/components/authoring/dialog/style/tab_design/styletab"/>
</items>
</tabs>
2. Verify that the component is included in the components section of the _rep_policy.xml file for the landing page template. This file defines the allowed components and their policies for the template.
3. Check if the filters present in the META-INF/vault/filter.xml file are excluding the component policy or any related files. The filters should not exclude the _cq_design_dialog folder or any other folders/files required for the component policy.
Finally, try clearing the dispatcher cache and browser cache after deploying the changes to the higher environment.