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Tenda AC9 – Current Time: 1999-12-31 18:31:13 (unsynchronized with internet time)

A have a Tenda AC9 (AC1200) and I can not change the date that appear on time settings, a do not have any manual changes or automatic internet one to synchronize, so this problem started 1 day ago and it appear like in title.

I reset and reboot the router and reconnect to internet service provider several time, change the time table, the issue is still there!

So i have problems with WiFi Schedule – The schedule takes effect only if the system time is synchronized with the internet time and – Automatic maintenance takes effect only if the system time is synchronized with the internet time.

Any idee to solve this strange problem?

Thank you

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