What package do you have?
What speed do you get with a wired connection?
Have you tried a factory reset? Hold in the pinhole at the rear of the router for at least 50 seconds and then release (the lights will flash while holding in the pinhole reset button after about 15 seconds) then allow 5 minutes for the router to reboot and re-sync the connection.
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Super Hub 4.0 (modem mode) - Gig1 Fibre FTTP - Asus RT-AX82U & Asus RT-AX56U with AiMesh setup
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