OK peeps, new finding here:
On my device admin page , only WAN
MAC is printed not PON MAC(hope I didn't confuse these terms)
I looked in to my device's dumped config file and it has mac address which matches with one shown on Self care ( btw there are many mac address defining entry in config file)
Also on the back of
ONT, PON MAC and WAN mac is written but again to my surprise the PON mac printed on the device is off by one digit than one shown on SelfCare
Also the moment i asked Varkey about ipv6 config since then my internet is down, although sad but great opportunity to catch the culprit in session log but the last session log(session end) is when my internet went down, also the MAC address match the PON MAC in ONT's config file
But,
When I was talking to varkey , that moment up total data usage was 1 TB with 30 something GB (s) usage for that day but now when I checked again it has crossed TB threshold with 1 TB 56 GB, according selfare on the day before Monday the data usage was 1 TB 12 GB on Monday it was 1 TB 56 Gb with total day usage of 30s something GB(I have posted in older post on this thread)
Subtracting the MB usage between two days , there 44 GB data difference between these two days , assuming I only used 40 GB max that day before my internet went out just for the sake of calculation where did that extra 4 GB went

. ( my internet is still down right now)
(PON led is green but admin page shows that ip PPPoE is down)
I am gonna complain tomorrow, so I need you guys advice to make my case rock solid !