Unable to start replication with External MySQL master

I am getting the below error while starting replication in RDS for external master. The Master is hosted in EC2 within the same VPC

mysql> show slave status\G *************************** 1. row *************************** Slave_IO_State: Connecting to master Master_Host: 54.89.210.126 Master_User: repl Master_Port: 3306 Connect_Retry: 60 Master_Log_File: TEST-mysql-bin.000002 Read_Master_Log_Pos: 846 Relay_Log_File: relaylog.000001 Relay_Log_Pos: 4 Relay_Master_Log_File: TEST-mysql-bin.000002 Slave_IO_Running: Connecting Slave_SQL_Running: Yes Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: mysql.plugin,mysql.rds_monitor,mysql.rds_sysinfo,innodb_memcache.cache_policies,mysql.rds_history,innodb_memcache.config_options,mysql.rds_configuration,mysql.rds_replication_status Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 846 Relay_Log_Space: 354 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: NULL Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 1045 Last_IO_Error: error connecting to master 'repl@54.89.210.126:3306' - retry-time: 60 retries: 1 Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 0 Master_UUID: Master_Info_File: mysql.slave_master_info SQL_Delay: 0 SQL_Remaining_Delay: NULL Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates Master_Retry_Count: 86400 Master_Bind: Last_IO_Error_Timestamp: 220228 08:14:01 Last_SQL_Error_Timestamp: Master_SSL_Crl: Master_SSL_Crlpath: Retrieved_Gtid_Set: Executed_Gtid_Set: Auto_Position: 0 Replicate_Rewrite_DB: Channel_Name: Master_TLS_Version: 1 row in set (0.00 sec)

In my Master log, I am getting unusual error. Please see below :

2022-02-28T07:22:21.141497Z 0 [Note] /mysqldatabase/product/binary/5.7.37/bin/mysqld: ready for connections. Version: '5.7.37-log' socket: '/mysqldatabase/TEST/admin/mysql.sock' port: 3306 MySQL Community Server (GPL) 2022-02-28T07:40:24.426990Z 4 [Warning] Hostname 'ec2-52-21-161-100.compute-1.amazonaws.com' does not resolve to '52.21.161.100'. 2022-02-28T07:40:24.427029Z 4 [Note] Hostname 'ec2-52-21-161-100.compute-1.amazonaws.com' has the following IP addresses: 2022-02-28T07:40:24.427034Z 4 [Note] - 172.31.70.67