HG612 Modem and Nest Wifi & VLAN

[#1]

I have a HG612 open reach modem flashed to the latest firmware on default settings.

I have a 2 point Nest Wifi kit.

I have a ftttc fibre broadband service.

I have connected the modem to DSL and the router to the modem and successfully PPPoe connected through the router to plusnet without issue..

For days no issues. Then intermittently the router drops random connections to devices. The WAN connection to plusnet remains stable throughout.

If I contact Google they says its a Vlan connection so its not supported and an unmanaged switch is needed to deal with the vlan tagging. 

My understanding is:

-nearly all broadband uses VLAN tagging in UK with 101 tag but this is terminated by the modem

-the HG612 default setting has VLAN tags disabled on the LAN

I think they are just dodging diagnosing the issue but....

I have gone round and round and round and round this issue with google and nearly at point of chucking it in bin and writing off £200 investment.

Is anyone, anywhere successfully using nest wifi in this configuration without stablity issues????

[#2]

Seems Google like to mention VLAN tagging, see https://community.plus.net/t5/Fibre-Broadband/VLAN-tagging-on-Fibre-connection/td-p/1761339 for example.

[#3]

Do you know if the problem got resolved?

I keep telling google theres no VLAN on the lan but they just ignore my feedback?

[#4]

Looks like that's it!

Google no tech knowledge and no customer care team say....

Good day! Sorry for the late response. May we know if your ISP or tech representative from your ISP knows how to identify VLAN Tagging?

We do apologize but we cannot process any replacement for the device because your ISP settings is unsupported. Please work with your ISP and get back to us once their settings is correct. Stay safe!
Thank you

...essentially if you can't get your modem to work with it or you experience any issues after successful setup Google don't support you if on a vlan wan connection ie. Most of UK fibre users

£200 down the drain

[#5]

I'd tell them that it's not fit for purpose under sale of goods / consumer rights.
Sounds like the whole system isn't fit for purpose in the UK DSL if they want to play that game.