Unable to synchronize system time, Pi-hole not working

[deHakkelaar]

@thofra01

netsh interface ip show dnsservers
... 89.101.251.228

Above DNS IP is not Pi-hole or running through Pi-hole:

pi@ph5b:~ $ dig +short -x 89.101.251.228
089-101-251228.ntlworld.ie.

And I should have supplied you also with the IPv6 version for that command:

netsh interface ipv6 show dnsservers

@thofra01

nslookup pi.hole
Server:  dns.mnd.iss.as9143.net
Address:  2001:b88:1002::10

And above one is also not Pi-holed.
The nslookup should have returned either the IP for your Asus router (in the "Server Address" field) or the IP for the Pi-hole host for proper blocking.
Also the "Name Address" reply would then be the IP for the Pi-hole host like below example:

C:\>nslookup pi.hole
Server:  ph5a.home.dehakkelaar.nl
Address:  10.0.0.2

Name:    pi.hole
Address:  10.0.0.2

Asus routers are a bit tricky to configure as can be seen from below thread:

Configuring DNS Server - LAN or WAN Settings on ASUS Router?

Hello - I am fairly new to pi-hole and had a quick question. I have an ASUS RT-AX86U router, and pi-hole (v5.2.4) running on R-Pi. I have everything set and it seems to be working well. So this question might be moot. Current setup: I am using the routers DHCP settings and configured the DNS to the pi-hole's IP on the router, and it is working correctly, and blocking ad's. [2021-01-24 09_35_59-Pi-hole - raspberrypi] But I am confused as to whether I setup the DNS settings in my router corre…

I also run an Asus router and decided to disable IPv6 support for the LAN side (dont need it anyway and complicates allot),
and disabled the DHCPv4 service on the Asus so that Pi-hole can take over:

How do I use Pi-hole's built in DHCP server (and why would I want to)?

Using Your Existing Router For Network-wide Ad Blocking You might not need to use Pi-hole's DHCP server: In many home environments, your router also functions as your DHCP server. In this case, you can often set Pi-hole to be the DNS server for your network clients in the router's DHCP (or LAN) settings page, which allows all of your network clients to block ads simply by connecting to the network. Setting it up this way is also what makes Pi-hole very powerful for network-wide ad blocking. …