Occurs to both my vodafone static IP SIM and EE Business Dynamic IP Unlimited Data SIM.

When setting a public DNS to DNS Settings (such as 8.8.8.8 or 1.1.1.1) and tapping 'save', the DNS Settings do not save and the default carrier DNS is used.

I know that the carrier is not blocking this as I have been able to use the above DNS Servers using other 4G/5G Routers such as the TP Link MR600 and Netgear Nighthawk M5.

When checking the Settings in Browser, my DNS Appears as:

Primary DNS:

109.249.185.228

Secondary DNS:

109.249.185.229

But it should be the one that I defined as part of settings.

Thank you.