pgpool 4.2.1 and postgres 11 streaming replication problem

I've setup a 2+2 pgpool and postgresql cluster. two pgpool nodes in active/standby configuration and a streaming replication between databases All seemed work fine until after some failover and online recovery tests took place. Suddenly I no longer able to see the "streaming" status from either "show pool_nodes" or "pcp_node_info commands. all users have the pg_monitor role granted. I'm unable to understand why I was able to see the "streaming" ( and async) repliction status , but not any more . Could someone help me to understand why? postgres=# show pool_nodes; postgres=# show pool_nodes; node_id | hostname | port | status | lb_weight | role | select_cnt | load_balance_node | replication_delay | replication_state | replication_sync_state | last_status_change ---------+----------+------+--------+-----------+---------+------------+-------------------+-------------------+-------------------+------------------------+--------------------- 0 | xxxxxxx | 5432 | up | 0.500000 | primary | 0 | false | 0 | | | 2021-03-16 01:37:19 1 | yyyyyy | 5432 | up | 0.500000 | standby | 0 | true | 0 | | | 2021-03-16 01:37:19 (2 rows) or from the pcp_node_info command [postgres@xxxxxxx ~]$ pcp_node_info --verbose -h localhost 0 Password: Hostname : xxxxxxx Port : 5432 Status : 3 Weight : 0.500000 Status Name : down Role : standby Replication Delay : 0 Replication State : <<<=== it is empty Replication Sync State : <<<=== it is empty Last Status Change : 2021-03-16 00:02:59 [postgres@yyyyyyyy ~]$ pcp_node_info --verbose -h localhost 1 Password: Hostname : yyyyyyyy Port : 5432 Status : 1 Weight : 0.500000 Status Name : waiting Role : primary Replication Delay : 0 Replication State : Replication Sync State :