are there any exchange problems http://usertools.plus.net/exchanges/mso.php
Just for info. Copied across from the other billing thread as this is a more appropriate place to put it all together.
Do you have a separate white Openreach fibre modem? If so you could try power cycling both the Openreach fibre modem and the BTHomeHub as described here.
Note: I see you have already tried the reset procedure for the modem. Did you reset the HomeHub as well as described?
After doing the power cycle you could try this self-help for checking the broadband connection.
Do check your service status though as imjolly suggested. If there is a known fault that lies at the street cabinet or exchange then no amount of resets in your home will cure it. You will have to wait for Openreach to fix it.
The official BT service status checking page.
And the DSL light is not lit
An obvious question, but have you checked that the DSL cable between the master socket and modem is still firmly in place at both ends?
The DSL light being off indicates no connection established from the Exchange-->StreetCabinet-->MasterSocket-->Modem for some reason? Don't think you can blame the HomeHub for that.
All checks have been done
What did the Problem with your internet connection? say?
It should have led you to something like this.
As it suggests, you need to phone the technical support (which is what you tried originally ). Make it very clear to them that you are on Infinity fibre broadband there is no DSL light on the white Openreach fibre modem. They should ask you to check cables and reset it, but just humour them and do it again so they can tick the box. If still not working then they should be able to try a line/connection test from their end.
It may well be that your broadband account has been mistakenly de-activated at some level or it might be a settings or hardware problem. Like the master socket, the white modem is the property of Openreach.