Newbie to HA, try to use duckdns but no luck

Newbie to Home Assistant.

Try to setup Duckdns for external connection but it become more problem for connection, now only can connect with computer browser (local) but not with iphone and ipad, and also no connection if using HA apps. Anybody any idea how to solve this problem, if this still not successful how do I going back into HA apps.

Thank you

Info for setting and connection.

Setting for duckdns in HA OS

accept_terms: true
certfile: fullchain.pem
keyfile: privkey.pem
token: 6c08*********************

ssl_certificate: /ssl/fullchain.pem
ssl_key: /ssl/privkey.pem

Modem / Router – Huawei EchoLife HG8245H5
Mash Router – TP-link Deco M5
Raspberry Pi 4B – 4gb

Connection / Deco M5 setup
Pi 4B to Deco M5 (wire to main Deco M5)
IP address – Dynamic IP
Ip address –
IP address reserved for HA 192.168.XX.XXX
Port Forwarding – Internal IP address 192.168.XX.XXX
Internal port - 8123
External port - 8123
Protocol – TCP