Running on unifibiz 800mbps

1. I got a new ax73 tp link to replace old router.

2. This ax73 is connected :
- 16 port gigabit switch
- 4 + 2 poe gigabit switch
- 5 port gigabit switch

All above is connected to lan port 1 2 3.
When i first tested ax73 connected to internet (connected via lan cat6 cable) on my network setting i could pair 1.0gb connection.everything was n perfect.

After i connected all those switches, now all my lan ports from is 100mbps no more 1.0gb/1000mbps

Things i did to double check :
1. Change cat 6 cables
2. Direct connect to lanport without switches connected to ax73 router.
3. Factory reset and reconfigured to connected to Internet.
4. Factory reset and skip all configuration just to check connection via lan cable still get 100mbps only (all ports on ax73).
5. Set evrything is setting laptop n router to 1000mbps full duplex.

All failed to get same results as first test.
Ok now anyone of you have encountered this. I think somehow something burnt of and capped my ax73 router lan port to 100mb.

Please id anyone got any solution or what did i do wrong.