@aishwaryab4598 It seems that truncating the tables 'rules.pr_sys_app_hierarchy_flat' and 'rules.pr_sys_app_ruleset_index' has caused the Application Explorer and Records Explorer to lose their data. These tables are used to store information about the application hierarchy and ruleset indexes, which are essential for displaying rule types and instances in the explorers.
To resolve this issue, you may need to rebuild the application and ruleset indexes.
It is recommended to consult with a Pega System Architect or Pega Support for further assistance in resolving this issue.
Please have a look at the following support document: