Guys I've tried what yall said and I'm still stuck, I've just installed maxis fiber, and they gave their maxis router which is the technicolor media access TG389AC, and the optical network terminal from Huawei, model HG8240H GPON, the router they gave is bad. So I bought tplink Archer C7 v2 and updated to latest Malaysian firmware. I connected the Lan cable from the Huawei ONT to archer wan port. I key in the username and password , it just shows connecting and refreshes the page and continue showing connecting. But if I connect the cable back to maxis router it connects to the Internet. So what's wrong here?

Yes I did follow all the guide here, even tried openwrt, all fail. I'm not sure why, example if the user name is 123456@home.maxis.com.my the password is 1234561 right?
So I can't figure out what's wrong.

Anyway I'm back to tplink firmware, this is what it shows after I set username and password. Even vlan tagging is 621 for Internet. I don't know why it won't connect in archer c7 but connects in maxis router


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This what it shows! Don't really understand what's written.