Enterprise manager 13.5 on Rhel 8 stuck at executing database-related prerequisites checks

Enterprise manager 13.5 on Rhel 8 stuck at executing database-related prerequisites checks.

all of these are set

alter system set "_allow_insert_with_update_check"=true scope=both;

alter system set session_cached_cursors=200 scope=spfile;

alter system set sga_target=800M scope=both;

alter system set pga_aggregate_target=450M scope=both;

alter system set "_optimizer_nlj_hj_adaptive_join"= FALSE scope=both sid='*';

alter system set "_optimizer_strans_adaptive_pruning" = FALSE scope=both sid='*';

alter system set "_px_adaptive_dist_method" = OFF scope=both sid='*';

alter system set "_sql_plan_directive_mgmt_control" = 0 scope=both sid='*';